A&P 1 All Chapters of Section 1

Which would likely be a greater threat to an animal's well being: a fracture of the mandible or a fracture of the occipital bone? Why?

A fracture to the occipital bone would be a greater threat because the spinal cord exits the skull through this bone and because it articulates (forms a joint) with the first cervical (neck) vertebra. The occipital bone is one of many bones that house the brain. Damage to this bone could affect various functions of the central nervous system.

5-3 What is a gland?

A gland is a cell or group of cells that has the ability to manufacture and discharge a secretion.

How does the negative feedback system control the secretion of many hormones?

A gland produces its hormone as a result of stimulation by another hormone. When the level of hormone from the first gland drops below needed levels, the second gland, the stimulating gland, produces more stimulating hormone, which stimulates the first gland to produce more of its hormone. The rising level of hormone from the first gland in the bloodstream eventually reaches the level required in the body. Once that level is reached, the production of stimulating hormone by the second gland is turned down. This reduces the stimulation of the first gland, causing it to produce less hormone. When the level of hormone from the first gland drops below what the body needs again, the second gland (stimulating gland) turns its production of hormone back up, which turns the production of hormone from the first gland back up, and the process continues.

What roles do the sensory receptor, sensory neuron, interneuron, and motor neuron play in the reflects arc?

A sensory receptor detects a change either in the external environment or within the body itself. Once stimulated to threshold, the sensory receptor sends an action potential (nerve impulse) along the sensory neuron to the gray matter of the spinal cord or brain stem. In the CNS gray matter, the sensory neuron synapses with other interneurons, which serve to integrate the incoming sensory impulse with other impulses from other sensory neurons. Finally, the integrated response of the reflex is sent out from the spinal cord or brain stem by the motor neuron, which ends at the target organ (muscle or endocrine gland).

Differentiate between acids and bases.

Acids - ionically bonded substances that release H+ when added to water. Also known as proton donors Bases - alkaline, ionically bonded. Release hydroxyl (OH-) ions when dissolved in water - proton acceptors - both are electrolytes because they transmit an electrical charge 1 acid --7 neutral (7.4 blood)--14 base

Differentiate between active and passive transport processes.

Active processes require ATP. Passive does not. Passive: diffusion, facilitated diffusion, osmosis, filtration Active: active transport, endocytosis (phagocytosis, pinocytosis, receptor mediated), exocytosis

What molecules in muscle act as the "batteries" to power the sliding of the actin and myosin filaments? What molecules function as the "battery chargers"?

Adenosine triphosphate (ATP) Creatine phosphate (CP)

Describe the functions of afferent and efferent nerves

Afferent - conduct nerve impulse toward the CNS from sensory receptors - called sensory nerve fibers Efferent - conduct nerve impulses away from CNS toward muscles and other organs - called motor nerve fibers - nerves can be sensory nerves, motor nerves, or mixed - most nerves in PNS are both

How does the tapetum aid low light vision?

After light has passed through the photoreceptors (the rods and cones) in the retina, it reflects off the tapetum and passes back through the photoreceptors again, stimulating them a second time. Therefore, most animals can see better in dim light than we can.

Differentiate between dense regular, dense irregular, and elastic connective tissues

All are Dense Fibrous Connective Tissue DENSE REGULAR Composed of tightly packed, parallel collagen fibers. The fibers lie in the direction of the force that is exerted on them, thereby giving the overall tissue tremendous tensile strength but only in one direction. - silvery or white -relatively avascular and slow to heal because nutrients and molecules have difficulty reaching the damaged tissue -fibroblasts form rows along the fibers and devote most of their energy to the manufacture of fibers. Little ground substance is produced - Makes up the tendons that attach muscles to bones, and ligaments that hold bones together at joints. Also composes the broad ribbons that sometimes cover muscles or connect them to other structures (sometimes in different directions to withstand more forces) DENSE IRREGULAR - Composed primarily of collagen fibers that are arranged in thicker bundles than those found in dense regular connective tissue. - Fibers are interwoven randomly to form a single sheet that can withstand forces from many different directions. - Found in the dermis of the skin and in fibrous coverings of organs such as the kidney, testes, liver, and spleen. Also forms the tough capsule of joints ELASTIC CONNECTIVE TISSUES - Consist primarily of yellow elastic fibers. May be arranged in parallel or in an interwoven pattern with fibroblasts and collagenous fibers interspersed. - Found in relatively few regions of the body. - In the spaces between vertebrae in the back bone, and places that require stretching such as the walls of arteries, stomach, large airways (bronchi), bladder, and regions of the heart. Lies beneath the transitional epithelium in the urinary tract and in the ligaments supporting the penis.

Differentiate between eccrine and apocrine sweat glands

Eccrine sweat glands Excretory portion consists of a simple, coiled tube located in the dermis or hypodermis Connects to surface by a long duct In dogs, only found in the deep layers of fat and the connective tissues of footpads Apocrine sweat glands Coiled, excretory portion buried in the dermis or hypodermis Single excretory duct Difference: empty into hair follicles instead of the surface of the skin In dogs, located in external ear canal, more in dogs with long hair (more hair also = more likely to get in ear canal infection)

How does the anatomy of a muscle or bone differ from its physiology? Which describes appearance and location and which describes function?

Anatomy deals with the form and structure of a muscle or bone. Physiology deals with their function.

Why do you suppose mild to moderate pain often does not appear to affect the mood or behavior of domestic animals significantly?

Animals do not seem to have the same kind of emotional reaction to pain that humans do. They often seem to hide it well. Hiding signs of pain is a survival instinct for most animals. An animal that shows signs of pain is showing signs of weakness that might encourage other animals, including predators, to attack it.

10-6 Where is aqueous humor produced? Where is it drained from the aqueous compartment of the eye?

Aqueous humor is produced in the posterior chamber by cells of the ciliary body. It is drained by the canal of Schlemm, and the fluid is returned to the bloodstream. The canal of Schlemm is a ringlike structure located at the edge of the anterior chamber at the angle where the iris and the cornea meet.

How do homeostatic mechanisms influence the health of an animal?

As conditions inside and outside change, homeostatic mechanisms influence the health of an animal by helping to maintain a fairly constant internal environment inside the body, making life possible.

Draw a picture of each of the 8 organelles described earlier

As you make your drawings, be sure to include the following organelles: mitochondria, ribosomes, rough and smooth endoplasmic reticulum, Golgi apparatus, lysosomes, proteasomes, peroxisomes, and vaults.

Differentiate between the autonomic and somatic nervous systems

Autonomic Nervous System - part of the nervous system that controls and coordinates automatic functions - heart rate, digestion, blood pressure, etc. - Autonomic motor sends impulses to smooth or cardiac muscles and glands - Autonomic sensory receive afferent sensory impulses from receptors that regulate body functions Somatic Nervous System - conscious, voluntary control of skeletal muscles - Somatic motor function - action caused by voluntary initiation of efferent impulses - Somatic sensory function - impulse sent to CNS from receptors in skin, muscles, eyes or ears - consciously perceived by brain

Differentiate between autonomic and somatic reflexes

Autonomic reflexes - regulate smooth muscle, cardiac muscle, and endocrine glands Somatic reflexes - involve contractions of skeletal muscles (Reflexes are rapid, automatic responses to stimuli designed to protect the body and maintain homeostasis)

List the components of the axial and appendicular skeletons

Axial: Skull, hyoid bone, spinal column, ribs, sternum Appendicular: Thoracic limb (front limb), pelvic limb (rear leg)

Name some examples of each of these kinds of synovial joint: Ball and socket joint Gliding joint Hinge joint Pivot joint

Ball-and-socket joint: shoulder and hip joints Gliding joint: carpus and tarsus Hinge joint: elbow joint and atlantooccipital joint (between the skull [occipital bone] and first cervical vertebra [atlas]) Pivot joint: atlantoaxial joint

List and describe common regional terms for the body.

Barrel - trunk of the body; formed by the rib cage and the abdomen Brisket - Area at the base of the neck between the front legs that covers the cranial end of the sternum Cannon - large metacarpal or metatarsal bone of hoofed animals Fetlock - joint between cannon bone (large metacarpal/metatarsal) and the proximal phalanx of hoofed animals Flank - lateral surface of the abdomen between the last rib and the hind legs Hock - tarsus Knee - carpus of hooved animals Muzzle - rostral part of the face formed mainly by the maxillary and nasal bones Pastern - area of the proximal phalanx of hoofed animals Poll - top of the head between the bases of the ears Stifle - femorotibial/femoropatellar joint; equivalent to human knees Tailhead - dorsal part of the base of the tail Withers - area dorsal to scapula

3-1 What are the basic cellular functions that define life?

Cells can grow, develop, reproduce, adapt, become influenced by outside stimuli, maintain a stable internal environment, and convert food into usable energy. Each cell carries vital genetic material that governs its own development, metabolism, and specialization.

List the components of the central nervous system and the peripheral nervous system

Central nervous system - brain and spinal cord, along central axis of body Peripheral nervous system - those components of the nervous system that extend away from the central axis outward toward the periphery of the - Cranial PNS originate from the brain - most PNS nerves are spinal nerves that extend from the spinal cord

Which category of temperature receptor is most critical to the long-term survival of an animal in very hot or very cold environmental conditions: the superficial receptors or the central receptors? (Hint: which is more critical to an animal's survival - keeping its skin and extremities from getting too hot or cold or keeping the core of its body from getting too hot or cold?)

Central receptors

How are centrioles structurally similar to cilia and flagella?

Centrioles are structurally similar to cilia and flagella because all consist of microtubules. Centrioles are small, hollow cylinders composed of microtubules. Cilia and flagella are composed of nine pairs of microtubules that encircle a central pair of microtubules.

What role does the centriole play in the formation of cilia and flagella?

Centrioles form the bases of cilia and flagella and in this role are known as basal bodies.

What part of the brain is critical for coordination, posture, and fine motor control? How does this part of the brain accomplish these responsibilities?

Cerebellum. The cerebellum compares the movement the body intends with the actual position of muscles and joints to determine if the intentions of the cerebral cortex are actually being carried out. If the movements are not being carried out accurately, the cerebellum will stimulate or inhibit muscles to fine-tune the movements.

What is the fluid called that bathes, cushions, and aids in transport of materials to and from the CNS?

Cerebrospinal fluid

9-5 What part of the brain is responsible for conscious thought and perception of sensations?

Cerebrum

Describe the structure and function of the components of the eyeball

Consists of 3 major layers: the outer fibrous layer, the middle vascular layer, and the inner nervous layer FIBROUS - The outer, fibrous layer of the eye that admits light to its interior and gives strength and shape to the eyeball Cornea: transparent window, admits light. no blood vessels, lots of pain sensors. Sclera: "white" of the eye, majority of the fibrous layer Limbus: the junction of the cornea and sclera VASCULAR (uvea) Choroid: between the sclera and retina. mainly pigment (dark melanin) and blood vessels that supply retina Tapetum Lucidum: highly reflective choroid in the rear of the eye in most domestic animals (not swine). light amplifier in low light, reflects light over photoreceptors a second time Iris: colored part of the eye, muscular diaphragm that controls the amount of light that enters Pupil: opening at center of iris; enlarges in low light (radially arranged muscle fibers) and gets smaller in bright light (circularly arranged muscle fibers) Ciliary Body: Ring shaped structure located immediately behind the Iris contains tiny muscle to the just the shape of the lens to allow near and far vision Ciliary Muscles: Multi unit smooth muscles contained in small processes called ciliary processes that are attached to the periphery of the lens by tiny suspensory ligaments. When they relax, the suspensory ligament pull on the periphery of the lens, stretching into a flattened shape. When they contract they move the ciliary body forward and inward (taking tension off the suspensory ligaments) allowing the lens to assume its natural more rounded shape. Suspensory Ligaments: attach the ciliary muscles to the periphery of the lens NERVOUS Fundus: caudal interior surface of the eye Retina: the camera of the eye, contains the actual sensory receptors for vision, the rods and cones MAJOR COMPARTMENTS OF THE EYEBALL Aqueous Compartment: in front of the lens and ciliary body, contains clear, watery Aqueous Humor (fluid) Vitreous Compartment: behind the lens and ciliary body, contains Vitreous Humor Anterior Chamber: space in front of the iris. Only portion of the eyes interior that we can see clearly without special instruments Posterior Chamber: space behind the iris in in front of the lens Canal of Schlemm: Ring like structure located at the periphery of the anterior chamber at the angle where the iris and the cornea meets. Drains the Aqueous humor LENS - Soft, transparent structure, elastic and biconvex (meaning that it bulges out on both sides). - Normal shape is fairly rounded but can be pulled into a flatter shape if tension is applied equally around its equator. - The front (rostral) surface of the lens is in contact with aqueous humor, and its back (caudal) surface is in contact with vitreous humor. - Main role is to help focus a clear image on the retina regardless of whether the object is close or far - Accommodation: The process where the shape of the lens is changed to allow close up and distant vision. - relaxed ciliary body muscles = suspensory ligaments put tension on lens = distance. - contracted = tension off suspensory ligaments = close up RETINA - Where the visual image is formed, sensed, and converted to nerve impulses that are decoded in the braid to reform the image in the conscious mind. - The whole reason the rest of the eye structures exist is to produce as accurate and clear an image as possible on the retina - lines most of the vitreous compartment - from outside in: pigment layer, photoreceptor layer, bipolar cell layer, ganglion cell layer, and a nerve fiber layer. (light goes through all to get to the photoreceptor layer) - bipolar and ganglion cells are neurons that integrate and relay nerve impulses from photoreceptor cells to the optic nerve Optic Disc: Where the nerve fibers converge and leave the eye Rods: More sensitive to light, but produce a coarse image in shades of Gray Cones: More sensitive to color and detail but do not function well in dim lights

In which skull bones are each of the following structures found? Cribriform plate External acoustic meatus Foramen magnum Frontal sinus Lacrimal sac Lower teeth Pituitary fossa Upper incisor teeth Upper cheek teeth

Cribriform plate: ethmoid bone External acoustic meatus: temporal bone Foramen magnum: occipital bone Frontal sinus: frontal bone Lacrimal sac: lacrimal bone Lower teeth: mandible Pituitary fossa: sphenoid bone Upper incisor teeth: incisive bones Upper cheek teeth: maxillary bones

What is cytosol and what kind of molecules are found in it?

Cytosol is the protoplasm of the cell. It is a viscous, semitransparent liquid composed of dissolved electrolytes, amino acids, and simple sugars. Proteins are also suspended in the cytosol and give it its thick, jellylike consistency.

3-3 What are the principal components of cytoplasm?

Cytosol, cytoskeleton, organelles, and inclusions

Differentiate between diffusion and facilitated diffusion.

Diffusion - Process of moving down the concentration gradient. High concentration to low concentration. Speeds up with heat Facilitated diffusion - large and non-lipid soluble molecules enter the cell via a carrier protein. Number of carrier proteins limits rates of facilitated diffusion

What is diffusion? Is it an active or a passive membrane process?

Diffusion is the passive movement of solute down a concentration gradient.

Which digit is the dewclaw on the front leg of a dog?

Digit 1

What is effusion? What is ascites?

Effusion is the escape of fluid from its normal vessels into a body cavity, where it may accumulate in large amounts. Ascites is the presence of an effusion in the peritoneal space of the abdominopelvic cavity and can be caused by a wide range of pathologic conditions (congestive heart failure, nephrosis, malignant neoplastic disease, and peritonitis among them).

How do electrolytes enter the cell?

Electrolytes enter cells via active transport (without the assistance of a concentration gradient).

Define the term "chromatin" and explain the relationship between chromatin and chromosomes.

"Material composed of DNA and proteins and makes up chromosomes" - During cell division chromatin condenses into super coiled X-shaped structures called chromosomes - In nucleoplasm of the nucleus, made up of DNA and globular proteins called histones - Single DNA strand winds around 8 histone molecules, forming a nucleosome - Histones keep DNA strand untangled and organized, and expose small sections (genes) to the outside. Called Gene Regulation

What are the 3 kinds of processes found on vertebrae and what are their characteristics?

(1) The single dorsally projecting spinous process and (2) the two laterally projecting transverse processes vary in size among vertebrae and act as sites for muscle attachment and leverage to move the spine and trunk. (3) The articular processes are located on the cranial and caudal ends of the vertebral arches and help form the joints between adjacent vertebrae.

Describe the structure and functions of the pituitary gland

- "Master endocrine gland" - directs other endocrine glands - Size of a pea (tiny), connected to the hypothalamus by a thin stalk - 2 separate glands: Anterior pituitary - rostral, glandular, produces 7 hormones when stimulated by the hypothalamus and direct feedback from target organs and tissues (also called adenohypophysis) Posterior pituitary - Caudal, nervous tissue, does not produce hormones - stores and releases 2 hormones that are produced in the hypothalamus and transported to pituitary along nerve fibers (also called neurohypophysis)

Describe the structure of the thyroid gland

- 2 lobes located on either side of the larynx - May be connected by a narrow band called the isthmus depending on the species - Composed of tens of thousands of tiny follicles where thyroid hormone is produced - Each follicle consists of a little sphere of simple cuboidal glandular cells surrounding a globule of the thyroid a whole home Precursor they have produced - Precursor = raw material for thyroid hormone - Thyroid gland is the only endocrine gland that stores large amounts of hormone precursor for later use

Explain how scientists believe the earliest cells may have formed on earth.

- 3 billion years ago - lightning and sun radiation caused methane (CH⁴), water and ammonia (NH³) to collide and split apart - organic molecules were formed and washed into the ocean by rain - proteins, lipids, and carbohydrates evolved and over time arranged themselves into cells

Describe the actions of a buffer system.

- Buffers help maintain a neutral pH by not allowing excessive H+ or OH- ions to accumulate - Buffers are weak acids and bases that do not completely ionize in water - Weak acids produce H+, a weak base product, and some remains a weak acid. If a strong base is added the H+ will attach and neutralize it, and the remaining weak acid will ionize further H²CO³-->H+ + HCO³- <--> 2H+ + CO3²- Carbonic acid -->hydrogen ions and bicarbonate (weak base) <--> hydrogen ions and carbonate

Explain the importance of cilia and flagella.

- Cilia - Move fluid, mucus, and debris across cellular surface - Upper respiratory tract, moves bacteria and mucus away from lungs - Oviduct, pulls egg away from the ovary into the opening of the oviduct - Flagella occurs singly, longer than Cilia, attached to single cells, propel cell forward by undulating - Sperm - Flagella move cell through fluid, Cilia moves fluid across cell surfaces - Both are extensions of the cell membrane

Describe the actions of enzymes.

- Enzymes speed up a chemical reaction without being used up or destroyed - Specific to the reaction that they catalyze and to their substrates that they act upon - Reactions often take place in a series, with one product being the substrate of the next reaction - Lock and key property Examples: Krebs cycle, electron transport system

Describe the structure and functions of the cytoskeleton.

- Flexible 3-dimensional frame for the cell - Changes with activities of the cell gives support and shape to cell, enables it to move, provides direction for metabolic activity, anchors organelles 3 types - Microtubules: thickest fibers, long hollow tubes radiate out from center of cell. Organelles can attach and be transported by motor proteins. Easily disassembled and reassembled to make new paths - Intermediate fibers: toughest and most pemanent, woven like a rope, high tensile strength, and can resist forces pulling on cell - Microfilaments: near cell surface, arranged in bundles and mesh works, composed of Actin and Myosin, help change cells shape, break apart during division, and form outpouchings and involutions - made when and where needed

Describe the consistency and molecular components of cytosol.

- Fluid of cell - Viscous, semi transparent liquid - Composed of dissolved electrolytes, amino acids, and simple sugars - Proteins suspended inside cytosol give it a thick, jelly like consistency (mostly enzymes important in metabolic activities of the cell)

List and describe the components of connective tissue

- GROUND SUBSTANCE - ranges from liquid to gel to solid The medium through which cells exchange nutrients and waste with the bloodstream. Acts as a shock absorbing cushion and helps protect the more delicate cells that it envelops. Its thick texture serves as an effective obstacle for invading micro organisms - FIBERS - COLLAGENOUS - Strong, thick strands composed of the structural protein collagin. collagen fibers are arranged in bundles of fibrils which are composed of microfibrils. Found in tendons and ligaments that are continually being pulled and stretched. Also known as "white fibers". Can be loose (around organs) or dense (tendons) - RETICULAR - Also composed of college and but they are not as thick. They are thin, delicate, and branched into complicated networks. Form a kind of "net" that provides support for highly cellular organs such as endocrine glands, lymph nodes, spleen, bone marrow, and liver. Also found around blood vessels common nervous, muscle fibers, and capillaries - ELASTIC - Composed primarily of the protein Alaskan. Branched and form complex networks but they lack the tensile strength of collagen's fibers. Composed of bundles of microfiber rules and because they are coiled they can stretch and contract like a rubber band. Tend to occur in tissues that are commonly subjected to stretching such as vocal chords, lungs, skin, and walls of blood vessels. Also referred to as "yellow fibers" - CELLS - FIXED CELLS - fibroblasts - Large, irregularly shaped cells that manufacture and secrete both the fiber and the ground substance characteristic of their particular matrix. They can reproduce and our metabolic we very active. Each connective tissue is characterized by a predominant fibroblast (such as osteoblasts in bone, fibroblasts in connective tissue). And cells mature and the matrix is formed the cells adopt a less active role and change to "-cyte" but if additional matrix is required later the cells can convert back to the "-blast" form. - adipocytes (fat cells) - Found throughout connective tissue, start out looking like fibroblasts but fill with lipid and become swollen with their nucleus pushed to one side. When they clustering groups they become known as adipose tissue. - reticular cells - Flat, star shaped cells with long out reaching arms that touch other cells comment for me netlike connections throughout the tissue they compose. Possibly involved in the immune response and the manufacture of reticular fibers. Primarily found in tissues that are part of the immune system such as lymph nodes, spleen, and bone marrow - WANDERING CELLS - mast cells - Oval cells that contain histamine and heparin and are involved in initiating inflammatory responses - leucocytes (white blood cells) - Found in blood and move into connective tissue in large numbers during times of infection - macrophages (fixed and wandering) - Massive, irregularly shaped phagocytizing scavengers that may be either fixed or transient in connective tissue. They engulf microbes, dead cells, and debris that are then digested in its lysosomes. Mobile macrophages are drawn to sites of infection or inflammation where they aggressively engulf microinvaders. Important part of the immune system and help tissues fight infections

Describe the structure of the basement membrane

- Nonliving network of fibers that anchor epithelial cells to connective tissue - Its strength and elasticity help prevent the cell from being torn off by a pressures such as stretching or rubbing - Acts as a partial barrier between epithelial cells and connective tissue; substances diffuse through - Oxygen, nutrients, and waste diffuse across the basement membrane to the epithelial cells or into the blood supply - Also called the "basal lamina"

Describe the process of endochondral bone formation and growth

- Starts with cartilage models of bones and replaces them with ossified bone tissue - Predominant method of bone formation in the body - Start out as rods of cartilage in developing fetus - Cartilages gradually removed as bone is created - Most cartilage has been replaced by the time an animal is born - Primary growth center in shaft (diaphysis) of long bones, secondary growth center in the ends (epiphysis) of the bone - Ephyseal (growth plates) allow long bones to lengthen

List the structures that comprise the hypodermis

- Thick layer below the dermis - It is a loose layer of areolar tissue that is rich with adipose cells, blood and lymphatic vessels, and nerves Contains a type of touch receptor called the pacinian corpuscles Contains a type of touch receptor called the Pacinian Corpuscle which is sensitive to heavy pressure The hypodermis is important because it permits the skin to move freely over underlying bone and muscle without putting tension on the skin that would result in tearin

List the physiologic factors that limit cell size.

- Volume to surface area: Restricted to a range of 10 to 30 um in diameter because of the relationship between surface area and internal volume of a cell - Nutritional requirements - a small cell has a small internal area relative to its surface area. A large surface area allows for greater absorption of nutrients - Limitations in governing capability - a single nucleus can control the metabolic activity of a small cell better than a large one

what organelles are ONLY in plant cells

-Cell wall -chloroplast -plasmodesmata -central vacuole

what organelles are ONLY in animal cells

-centrioles -lysosomes -cillia and flagella

smooth endoplasmic reticulum (SER)

-connected to nucleus -creates and stores lipids -tubes

rough endoplasmic reticulum (RER)

-connected to nucleus -synthesize and package proteins -looks like sheets with many holes and bumps (ribosome)

flagella

-connected to plasma membrane (outside) -helps cell move in its environment -long rod like tail

cillia

-connected to plasma membrane (outside) -used to move liquids past outside of cell so it can move in its environment -thin hair-like

mitochondria

-cytoplasm -performs cellular respiration, creates energy -oval

ribosomes

-found all around -make proteins based info from chromosomes -small round

lysosomes

-in cytoplasm -key organelle in digestive system, breaks materials down and removes waste -round/oval

nucleus

-in cytoplasm in center of cell -acts like brain of cell, controls and reproduces -oval

golgi apparatus

-in cytoplasm near ER -package and store macromolecules (mainly proteins), builds lysosomes -sacks or flaps, look like a stack of pancakes

vesicles

-in cytoplasm, around outside of golgi apparatus -transports materials from one place in cell to another, created by plasma membrane -round

cytoskeleton

-in cytoplasm, connected to membrane -creates shape of cell, helps transport materials in and out of cell also within the cell -no shape

nucleolus

-in nucleus -combines proteins with rewritten RNA -round

peroxisomes

-next to nucleus but closer to edge -breaks down fatty acid chains into usable materials -sphere shape but can be changed

Test Yourself 6-1 Why is skin important? Can you think of 6 important functions of skin?

1. 1. Skin covers and protects underlying structures. 2. By forming a critical barrier between the delicate inner workings of the body and the harsh elements of the external world, skin prevents desiccation and reduces the threat of injury. 3. Skin assists in the maintenance of normal body temperature via sweating and shivering and the presence of features such as hair and sebaceous glands. 4. Skin excretes water, salt, and organic wastes. 5. Skin is an important sensory organ that takes in information from the environment through touch and pressure and conveys this input to regions of the central nervous system. 6. Skin is engaged in the synthesis of vitamin D and the storage of nutrients.

What is a chemical reaction?

1. A chemical reaction is a change or transformation in a substance during the formation or breaking of chemical bonds.

How does ATP differ from nucleotides?

1. ATP is an RNA nucleotide containing the nitrogen base adenine with two additional phosphate groups attached.

Which type of compound is known as a proton donor: acid or base?

1. Acid

Cell theory

1. All living things are composed of one or more cells 2. Cell are the basic units of structure and function in organisms 3. all cells come from existing cells

What are the 3 cycles of hair growth?What are the 3 cycles of hair growth?

1. Anagen is the time of hair growth 2. Telogen occurs when the maximum length of hair is achieved, the hair stops growing, the hair follicle shortens, and the hair is held in a resting phase. 3. Catagen is the period of transition between the anagen and telogen phases.

List and define the terms used describe shape and surface features of bone

1. Articular surfaces - joint surfaces - smooth area where bones come in contact to form joints. Covered with hyaline cartilage called articular cartilage CONDYLE - large, round articular surface. Cylindrical shape. - Distal end of humorous and femur, occipital bone HEAD - spiracle articular surface on proximal end of long bone - Proximal end of humerous, femur, ribs FACET - flat articular surface. Rocking joint movement - Carpal and Tarsus, vertebrae, radius and ulna 2. Processes - lumps, bumps and other projections on bones. Smooth in joints, rough where muscles attach 3. Holes and depressed areas FOREMAN - hole, something important passes through (vessels, nerves) FOSSA- depressed or sunken area on surface of bone. Usually occupied by muscles or tendons

How is an ion different from an atom?

1. Atoms are neutral. They contain the same number of protons as electrons. An ion is an electrically charged particle produced by either removing electrons from a neutral atom to yield a positive ion or adding electrons to a neutral atom to yield a negative ion.

What are the three elements found in all lipids?

1. Carbon, hydrogen, and oxygen

What three elements are found in all carbohydrates?

1. Carbon, hydrogen, and oxygen

What four attributes characterized epithelial tissue in general?

1. Epithelial cells are polar: that is, they have a sense of direction relative to surrounding structures. Each epithelial cell has an apical surface and a basal surface, which are quite different from each other. The apical surface is the side of the cell that faces the lumen or body cavity, and the basal surface is the side of the cell that faces the underlying connective tissue. 2. Epithelial cells have lateral surfaces that are connected to neighboring cells by junctional complexes. These junctions bring the cells into close apposition to one another, leaving little room for extracellular matrix. The matrix that surrounds epithelia therefore exists in very small quantities, if at all. 3. All epithelial cells lack blood vessels or capillaries. They are avascular and rely on underlying connective tissue to provide oxygen and nutrients. 4. Although some epithelia lack nerves (for example, those in the stomach, intestines, and cervix), most epithelial cells are innervated and provide valuable sensory input.

List and describe the 3 classifications of joints

1. Fibrous joint - immovable (synarthroses) 2. Cartilaginous joint - slightly movable (amphiarthroses) 3. Synovial - freely movable Hinge - flexion/extension Gliding - rocking; mainly flexion/extension, some abduction/adduction Pivot - only rotation - Atlas/axis joint Ball and socket - flexion, extension, abduction, adduction, rotation, circumduction

List 7 functions of connective tissue

1. Forms metabolic and structural connections between other tissues. 2. Forms a protective sheath around organs. 3. Helps insulate the body. 4. Acts as a reserve for energy. 5. Provides the frame that supports the body. 6. Composes the medium that transports substances from one region of the body to another. 7. Plays a vital role in the healing process and in the control of invading microorganisms.

Describe 3 types of cartilage. What are their differences and similarities?

1. Hyaline cartilage: Hyaline cartilage is the most common type of cartilage in the body. It is composed of closely packed collagen fibers that make it tough but more flexible than bone. Macroscopically, hyaline cartilage resembles a blue-white, frosted ground glass. It is found in the growth plates of long bones, where it supports continued bone development and the extension of bone length. Hyaline cartilage is the most rigid type of cartilage and is enclosed within a perichondrium. 2. Elastic cartilage: Elastic cartilage is similar to hyaline cartilage but contains an abundance of elastic fibers, which form dense branching bundles that appear black microscopically. Elastic cartilage is found in the epiglottis of the larynx and in the pinnae (external ears) of animals. 3. Fibrocartilage: Fibrocartilage usually is found merged with hyaline cartilage and dense connective tissue. Like hyaline cartilage, it contains thick bundles of collagen fibers, but it has fewer chondrocytes and lacks a perichondrium. Fibrocartilage is found in the spaces between vertebrae of the spine, between bones in the pelvic girdle, and in the knee joint.

What three factors play a role in the control of cell division?

1. Normal cells stop dividing when they come into contact with surrounding cells. This phenomenon is called contact inhibition. 2. Growth-inhibiting substances may be released from cells when their numbers reach a certain point. 3. A number of checkpoints are reached during cell division when the cell reassesses the division process. These checkpoints occur during the G1 and G2 phases of interphase.

How does a nucleotide differ from an amino acid?

1. Nucleotides are the building blocks of nucleic acids such as DNA, but amino acids are the building blocks of proteins.

List and describe the characteristics used to classify different epithelial tissues

1. Number of layers of cells - simple (one) or stratified (more than one) 2. Shape of cells - squamous, cuboidal, or columnar (based on top layer of cells) 3. Presence of surface specializations - microvilli (increased absorption), cilia (move substances), keratin (protection and waterproofing) keratinized stratified squamous epithelium - skin nonkeratinized stratified squamous epithelium - lining of mouth

What is the difference between organic and inorganic compounds?

1. Organic compounds are molecules that contain hydrocarbon chains and groups (hydrogen and carbon) and usually are covalently bonded. Inorganic molecules, on the other hand, do not contain hydrocarbon chains and groups and are often ionically bonded.

List the functions of bone

1. support body 2. Protect delicate organs and tissues 3. Act as levers for the skeletal muscles to move the body 4. Store minerals, principally calcium 5. Some bones serve as sites for blood cell formation (hemopoiesis) in red bone marrow

List the early discoveries of the 17th, 18th, and 19th centuries that led to our modern understanding of cells.

1655 - Hooke described 'cells' in cork. 1838 - Schleiden and Schwann proposed cell theory. 1858 - Rudolf Virchow expounds his famous conclusion: that cells develop only from existing cells [cells come from preexisting cells] 1879 - Flemming described chromosome behavior during mitosis.

What are the four properties of water that make it so necessary for life?

2. (1) Water is the universal solvent. (2) Water is an ideal transport medium. (3) Water has a high heat capacity and a high heat of vaporization. (4) Water is used for lubrication.

What is a chemical symbol?

2. A chemical symbol uses a letter or letters to refer to elements. Chemical symbols are derived from the element's name in English, Latin, or Greek.

How does an ionic bond differ from a covalent bond?

2. A covalent bond is the bond formed when atoms share electrons. An ionic bond is formed when electrons are transferred from one atom to another.

What are the building blocks for proteins?

2. Amino acid

How does ATP supply a cell with energy to do work?

2. As a nutrient (for example, glucose) is catabolized, the energy created is stored in ATP molecules. ATP stores this energy in the bonds between its phosphate groups. When these bonds are broken, that energy is released from the ATP molecule. To use the energy stored in ATP, enzymes must move the terminal phosphate group to another molecule. The receiving molecule is then called phosphorylated and temporarily has energy to do some work. During this process the ATP molecule loses a phosphate group and becomes ADP. Another phosphate group can be used, resulting in the creation of a molecule of AMP. As more glucose and other nutrients are metabolized, phosphate groups are joined to AMP, creating a renewed source of ATP.

Which atom makes up the backbone of all lipid molecules?

2. Carbon

Where are anal sacs found and what is their importance to animals?

2. Cats and dogs have anal sacs that are located at the 5 and 7 o'clock positions relative to the anus. They are connected to the lateral margin of the anus by a small, single duct. The anal sac is lined with sebaceous and apocrine glands and acts as a reservoir for the secretions produced by these glands. When the animal defecates or becomes frightened, some or all of the anal sac contents are expressed. In this way, feces become coated with the secretions stored in the anal sac, and the unique smell of the animal is transferred to the environment. Thus defecation serves the dual purpose of elimination and of marking a territory or attracting a mate.

How are paw pads and the planum nasale different from other regions of skin?

2. Digital pads are formed by thick layers of fat and connective tissue that bear the weight of the animal. The pad's outer surface is the toughest and thickest skin in the body. It is often pigmented and is composed of all five epidermal layers. Of these five layers, the outermost epidermal layer, the stratum corneum, is thicker than all the others combined. This tough outer skin together with insulating fat forms a protective barrier against abrasion and thermal variances, enabling the animal to walk on rough surfaces, hot roads, and cold snow. The surface of the pad feels rough, and an uneven surface is visible to the naked eye. The pad is composed of exocrine sweat glands and lamellar corpuscles. Histologically, the ducts from these sweat glands can be seen passing through the dermis to the stratum basale of the epidermis. Their glandular excretion is then excreted onto the surface of the pad. The planum nasale is usually pigmented and appears to be a tough, thick region of integument histologically; however, the planum nasale in the dog is composed of only three epidermal layers, with the stratum lucidum and stratum granulosum absent. The outermost layer, the stratum corneum, is composed of only four to eight cell layers, surprisingly thin considering the exposed location of the nose and its heavy use, particularly in the dog. The epidermal surface of the planum nasale is divided by deep surface grooves, giving it the appearance of being composed of multiple plaques. As with other regions of the skin, the dermis and epidermis interdigitate to form an irregular line of attachment that includes dermal papillae. Although often moist from nasal secretions and licking, the planum nasale in the dog contains no glands in the epidermis or dermis. However, in the sheep, pig, and cow, tubular glands are found.

What is an electrolyte, name some examples.

2. Electrolytes are substances that have the ability to transmit an electrical charge. 3. Sodium, potassium, and calcium are examples of electrolytes.

What is the name of a simple sugar?

2. Monosaccharide

What three parts compose a nucleotide?

2. Nucleotides are composed of a nitrogenous base, a 5-carbon (pentose) sugar, and a phosphate group.

What are the three types of chemical reactions?

2. Synthesis reaction: A new, more complex chemical is made from multiple simpler chemicals. Decomposition reaction: A complex substance breaks down into its simpler parts. Exchange reaction: Certain atoms are exchanged between molecules. It is a combination of a synthesis and a decomposition reaction.

What is a peptide?

4. A peptide is a molecule consisting of two or more amino acids in which the carboxyl group of one acid is linked to the amino group of the other.

Why does hair turn Gray and then white as animals age?

4. As animals age, melanin production decreases, and the hair begins to turn gray. White hair is formed when the cortex loses its pigment entirely and the medulla becomes completely filled with air.

Explain the structure of DNA.

4. DNA molecules consist of two parallel strands of the nucleotides A, G, C, and T. The strands are connected by hydrogen bonds between the nitrogenous bases. Each nitrogenous base can hydrogen bond with only one other specific nitrogenous base. Adenine can bond only with thymine, and guanine can bond only with cytosine. The two strands of bonded nucleic acid twist around each other in a spiral called a double helix. The order of the nucleotides is unique to each individual and is carried in every cell of the individual.

What important function do hydrogen bonds perform in organic and inorganic chemicals?

4. Hydrogen bonds are primarily formed between molecules as an electrostatic attraction. Hydrogen bonding is the key to water's unique properties as a universal medium. Hydrogen bonds can also form between parts of the same molecule, giving it increased stability. The shape of DNA and large proteins, for example, is maintained by hydrogen bonds within the molecule.

How does a weak acid as a buffer?

4. It helps the cell maintain a neutral pH by not allowing excessive hydrogen or hydroxyl ions to accumulate. In water, a weak acid will initially ionize into: (1) free hydrogen (H+) ions, (2) a weak base product, and (3) remaining intact weak acid molecules. The pH of the solution is not changed much because some of the chemical remains in acid form and some remains in the form of a weak base.

What is the function of lipid in the body?

4. Lipids are used in the body for energy and are stored in fat for future energy needs. Lipids also serve as chemical messengers in the form of some hormones.

What is another name for a complex, multiunit carbohydrate?

4. Polysaccharide

What is the electronic charge of each particle?

4. Protons have a positive electrical charge, neutrons have no electrical charge, and electrons have a negative electrical charge.

How is the skin of hairy animals different from that of humans?

4. Skin covered with fur usually consists of three epidermal layers rather than five. These layers are the stratum basale, stratum spinosum, and stratum corneum. The stratum granulosum and stratum lucidum are generally missing. A few regions of five-layered epidermis can be found in furry mammals, but these are usually seen in places where the keratinization process has slowed and the skin is very thick. The surface of "hairy skin" is covered in scalelike folds. Hair emerges from underneath the scales and is directed away from the opening of the hair follicle. In dogs the hair is organized in clusters of three follicles per scale. Periodically throughout the surface of the epidermis a knoblike elevation can be seen. This is called a tactile elevation, or epidermal papilla. Each tactile elevation is usually associated with a tactile hair. These special hairs are called tylotrich hairs, and they are important in the perception of touch.

What factors influences the rate of chemical reactions?

4. The rate of a chemical reaction is influenced by: (1) the availability of the reactants, referred to as the concentration of reactants. The more reactants that are available, the more likely they will come in contact and be able to react with one another. (2) The temperature of the environment. When the temperature increases, the speed of molecular movement increases and the chance of molecules meeting improves. Temperature also increases the velocity at which the reactants meet, and the velocity provides the energy for the reaction. (3) Activation energy is the energy required for the reaction to happen. Some reactions have a higher activation energy and require an input of more energy for the reaction to occur. These reactions will occur at a slower pace. (4) Certain reactions require the presence of a catalyst. In living organisms, catalysts are usually special proteins that hold the reactants together so they may interact. The catalyst protein is not destroyed or used up by the reaction, and the reaction speed is increased when there are more catalyst proteins present. These special catalyst proteins are called enzymes.

What features does carbon possess that makes it well suited for creating life chemistry of living creatures.

5. Carbon is electrically neutral and can form four covalent bonds with other atoms, including other carbon atoms. It can take on a linear structure or a ring structure from which functional groups extend.

Why is DNA important to life?

5. DNA is the molecule that contains all the instructions needed by the cell to build protein. These instructions determine the shape and function of every tissue in the body and, therefore, the shape and function of the living organism.

How does an enzyme work?

5. Enzymes speed up or catalyze chemical reactions without being destroyed or altered. Enzymes are specific to the reaction they catalyze and the substrates (the substances they act upon) they use.

Which particles are in the nucleus of an atom?

5. Protons and neutrons

What factors stimulate contraction of the arrector pili muscle? Why is this muscle important?

5. The sympathetic nervous system stimulates the contraction of the arrector pili muscles when an animal is frightened or cold. This reaction is a defense mechanism designed to make the animal appear bigger and therefore less vulnerable to potential predators. In addition, hair that stands erect can better trap insulating layers of air than can nonerect hair, so animals with erect hair coats stay warmer than animals with flat coats. The arrector pili muscle also is responsible for forcing sebum from the sebaceous gland, which helps keep the integument moist and supple.

How is the dermis different from the epidermis?

5. Unlike the epidermis, which is primarily cellular, the dermis is highly fibrous. It is composed of dense, irregular connective tissue that contains collagen, elastic, and reticular fibers. Hair follicles, nerve endings, glands, smooth muscle, blood vessels, and lymphatics are all found in the dermis as well, creating a rich and interesting tissue community. Fibroblasts, adipocytes, and macrophages also are present and represent the most commonly found cellular elements. The dermis is a tough layer that binds the superficial epidermis to the underlying tissues. It represents the "hide" of the animal and is used to make leather.

Define the term "functional group".

6. A functional group is the reactive part of a molecule that determines the molecule's chemical activity.

How many electrons shells would an atom have if it had 4 electrons?

6. Two

What is a mixture?

7. A mixture is a combination of two or more ingredients that are chemically unchanged when combined with one another. Mixtures can be homogeneous and heterogeneous.

List three types of mixtures. How is each type similar or different from the other?

8. There are three types of mixtures: solutions, colloids, and suspensions. Solutions are homogeneous mixtures of various substances that can occur as gases, liquids, and solids. The size of the solutes is very small, consisting only of a few atoms. Colloids are also called emulsions and are translucent, heterogeneous mixtures that contain larger-sized solutes than those found in solutions. The solutes do not precipitate and remain suspended, which allows colloids to reflect light. Suspensions are heterogeneous mixtures containing large solutes that readily separate from the solution when stationary.

How are compounds & mixtures different from one another?

9. A compound includes two or more elements that are chemically bonded to one another via covalent or ionic bonds. The elements are present in a specific ratio, which is consistent for a particular compound.

What is a hormone target?

A cell that has receptors for a particular hormone is referred to as a target of that hormone.

What are codons and what role do they play in transcription?

A codon is a set of three adjacent nucleotides in an mRNA molecule that specifies the incorporation of an amino acid into a peptide or polypeptide chain or that signals the end of peptide synthesis.

What are GAGs and what role do they play in connective tissue? Why do you suppose animals with joint injuries are sometimes given dietary supplements of GAGs

Glycosaminoglycans (GAGs) are the ground substance in soft connective tissue. They are made of unbranched chains of glycoproteins. Animals with joint injuries are sometimes given GAGs because they may help with joint healing. Joints contain hyaluronic acid, which is the most commonly found GAG in connective tissue. GAGs are large molecules that help to orient the formation of fibers within the tissue during healing.

What is granulation tissue? Why is it important in the healing process?

Granulation tissue is a bright pink tissue that forms as macrophages work to clear debris from beneath the overlying blood clot or scab. Composed of a layer of collagen fibers manufactured by fibroblasts, granulation tissue is richly infiltrated with small permeable capillaries that have branched off existing capillaries in the deeper layers of the damaged tissue. These new tiny vessels push up into the bed of collagen fibers and provide rich supplies of nutrients and oxygen to hard-working cells such as fibroblasts, macrophages, and neutrophils. Macroscopically, the capillaries appear to be minute granules and are therefore called "granulation tissue." Granulation tissue produces bacteria-inhibiting substances, making it highly resistant to infection.

What are intercalated disks and why are they important to the functioning of cardiac muscle?

Intercalated discs are the attachments of the end of one cardiac muscle cell to the end of another cardiac muscle cell. They secure the cells together and transmit impulses from cell to cell, thus coordinating the contraction of large groups of cells.

List and describe the visceral senses

Interior body sensations - hunger - thirst - stretching of internal organs (causes pain except in the bladder) - pleura and peritoneum have no sensation as long as they slide smoothly over each other, otherwise are painful

Does ADH help promote or prevent the loss of large amounts of water in the urine? What effect would the inhibition of ADH release have on the body?

It helps prevent the loss of large quantities of water in the urine. Inhibition of ADH would cause more water to flow out of the body in the urine.

Why is cartilage limited in thickness and slow to heal?

It is limited in thickness because nutrients diffuse from the surrounding perichondrium through the matrix to the chondrocytes. Therefore, chondrocytes that are farthest away from the perichondrium are potentially less well nourished than cells close to it. Cartilage is slow to heal because it is avascular.

Is an animal with a body condition score (BCS) of 3/9 too fat or too skinny?

It is too skinny. A BCS of 5/9 is ideal. Lower values indicate the animal is underweight and higher values indicate the animal is overweight.

List the hormones produced by the kidneys, stomach, small intestine, placenta, thymus, and pineal body

KIDNEYS Erythropoietin - Stimulates red bone marrow to increased production of oxygen carrying red blood cells STOMACH Gatrin - Produced by the stomach wall and acts on the stomach wall, stimulated by the presence of food. Stimulates stomach glands to secrete hydrochloric acid and digestive enzymes and encourages muscular contractions of the stomach wall SMALL INTESTINE Secretin - Stimulates the pancreas to secrete fluid rich in sodium bicarbonate into the duodenum to neutralize the acidic chyme from the stomach Cholecystokinin - Stimulates the release of digestive enzymes from the pancreas into the duodenum PLACENTA Small amounts of estrogen and progesterone Chorionic gonadotropin - Detection is the basis for pregnancy tests in humans and horses Relaxin - Helps relax ligaments between the bones around the birth canal in preparation for parturition THYMUS Thymosin Thymopoietin - Both cause primitive cells in the thymus and other lymphoid organs to be transformed into T lymphocytes. Also called T cells. They are an important part of the animal's cell mediated immunity that produces killer cells that directly attack foreign invaders PINEAL BODY Melatonin - Affects moods and wake-sleep cycles. - May also play a role in the timing of seasonal estrous cycles in some species

Why would keen hearing be important to the survival of a potential prey animal? Why would it be important to a predator?

Keen hearing allows a potential prey animal to hear movements caused by its predator and escape. Keen hearing allows a predator to hear the slightest movements made by its potential prey so that it can track and find it.

11-7 Why are patients with kidney failure often anemic?

Kidney failure patients are often anemic because of their deficiency of erythropoietin produced by the failing kidney, which normally stimulates red bone marrow to increase production of oxygen-carrying red blood cells.

Differentiate between a molecule and a compound.

Molecule - smallest unit of a compound that retains the properties of that compound. Formed when 2 or more atoms of the same element bond (O²) Compound - composed of 2 or more different elements - Properties are different from the properties of the elements that make up the compound (NaCl)

What is the relationship between the myelin sheath and the nodes of ranvier?

Nodes of Ranvier are small gaps in the myelin sheaths. The nodes of Ranvier and the myelin work together to enhance the conduction of stimuli.

What is a nucleotide and how is it structured?

Nucleotides are the building blocks or units of DNA and RNA molecules and are composed of three subunits: a nitrogenous base, a five-carbon sugar, and a phosphate group. DNA and RNA nucleotides are linked to form a "backbone" of alternating sugar and phosphate groups. The nitrogenous bases project out of this backbone.

How does the basement membrane act as a partial barrier between the epithelial cell and the underlying connective tissue?

Oxygen and nutrient molecules are supplied to the epithelial cells by diffusing through the basement membrane from capillaries in the underlying connective tissue. Similarly, nutrient substances that are absorbed and waste that is excreted by the epithelium diffuse across the basement membrane into the blood supply of the connective tissue.

Describe the unique features of the paw pads and planum nasale

PAW PADS Outer surfaces the toughest and thickest skin on the body Often pigmented and composed of all 5 epidermal layers Stratum corneum is thicker than all the others combined The insulating fat and tough outer skin form a protective barrier against abrasion and thermal variations The insulating fat and tough outer skin form a protective barrier against abrasion and thermal variations Covered in minute conia papillae Pad also has exocrine sweat glands and lamellar corpuscles which excrete onto the surface of the pad Carpal pads: causal surface of wrist Metacarpal and metatarsal pads: Central weight-bearing pads of the foot Digital pads: Protect each of the digits careful a letter have one of them you can't have both PLANUM NASALE Top of the nose in cats, pigs, sheep, and dogs Called muzzle or Planum Nasolabiale in cows and horses Composed of 3 epidermal layers: lucidum and granulosum are missing Stratum corneum is only 4-8 cell layers thick Surface is divided by deep grooves which gives it the appearance of being composed of multiple polygonal plaques. Dermis and epidermis interdigitate to form an irregular line of attachment that includes dermal papillae No glands in dogs Sheep, pigs, and cattle have glands

What is the general effect of sympathetic nervous system stimulation on visceral smooth muscle? What is the effect of parasympathetic nervous system stimulation?

Parasympathetic nerve stimulation increases smooth muscle activity.

What two hormones play important roles in maintaining homeostasis of blood calcium levels in the body? Which one prevents hypercalcemia? Which prevents hypocalcemia?

Parathyroid hormone (PTH), also called parathormone, and calcitonin. PTH helps prevent hypocalcemia, and calcitonin helps prevent hypercalcemia.

Describe the process of osmosis.

Passive movement of water through a semi permeable membrane into a more concentrated solution. Stops when concentration is equal on both sides of the membrane equilibrium Osmotic pressure - the force of water moving from one side of the membrane to the other Oncotic pressure - difference between the osmotic pressure of blood and the osmotic pressure of interstitial fluid or lymph. Maintains fluid balance between blood or lymph in vessels and fluid in surrounding tissues

What is the largest sesamoid bone in the animal body?

Patella

Which chemical hormone group(s) bind to receptors on the target cell membrane? In the cytoplasm or nucleus?

Peptide hormones and monoamine catecholamine hormones bind to receptors on the target cell membrane. Steroid hormones and monoamine thyroid hormones bind to receptors in the cytoplasm or nucleus.

What are the 3 main chemical groups of hormones?

Peptide hormones, steroid hormones, and monoamine hormones

List the components of the neuron

Perikaryon - cell body Dendrites - receives impulses Axon - conducts impulse away from cell Neuralgia cells - support neurons

7-6 Name the bones of the pelvic limb from distal to proximal

Phalanges, metatarsal bones, tarsal bones, fibula, tibia, patella, fabellae, femur, and pelvis

How do glands developed embryologically?

Multicellular glands form during embryonic development from the infolding of a layer of epithelial cells. Initially, these "invaginations" form ducts and tubules that maintain contact with the surface epithelium. In the course of development, some of the glands lose the ducts and become separated from the parent epithelial sheet. In this way, glands are derived from epithelium.

5-7 In what ways are muscle fibers uniquely adapted for contraction?

Muscle fibers are composed of specialized proteins called actin and myosin, which are arranged into microfilaments. Contraction, or shortening, of the muscle cell occurs when the microfilaments slide over one another like the bars in an old-fashioned slide rule. In this way, the cells change shape and can be made shorter or longer.

8-1 What is muscle?

Muscle is one of the four basic tissue types in the body

What is myoglobin and why is it important?

Myoglobin is a large protein in muscle that can store oxygen for times, like during strenuous exercise, when more oxygen is needed by the muscle.

Which contractile protein filaments make up the dark bands of skeletal muscle cells? Which make up the light bands?

Myosin myofilaments Actin filaments

List the steps in the synthesis of proteins.

NUCLEUS: TRANSCRIPTION 1. RNA polymerase Finds to ADN a molecule and initiate separation of the double helix. Specific section of DNA, called a gene, is exposed 2. RNA polymerase moves along the DNA strand and coordinates the pairing of nucleotides to corresponding DNA nucleotides. The RNA nucleotides are linked to one another to form a strand of mRNA 3. When RNA polymerase reaches the end of the gene, the newly formed mRNA molecule is released and travels through the nuclear envelope to the cytoplasm 4. The separated strands of DNA are reunited to form a double helix once again CYTOPLASM: TRANSLATION 1. A ribosome binds to the beginning of the mRNA strand. 2. Transfer RNA molecules move into the vicinity of the ribosome. The anticodon is paired with the appropriate codon on the mRNA molecule. 3. The amino acid carried by the tRNA molecule is released and linked to the neighboring amino acid. 4. The ribosome continues to move along the mRNA molecule until all of the codons have been paired. 5. As the developing chain of amino acids lengthens, it coils and fold into the structure of a functional protein 6. When translation is complete, the new protein is released and later modified. The mRNA, tRNA, and ribosome are free to repeat the process and form more of the same type of protein

What is the common name for the distal sesamoid bone in a horse?

Navicular bone

Describe the effect of nerve simulation on the functioning of visceral smooth muscle versus multi-unit smooth muscle

Nerve stimulation does not initiate smooth muscle action; it modifies it.

Describe the structures and functions of neurons and neuroglia

Neurons = nerve cells - conduct impulses and respond to stimuli - Cell body - Soma or parikaryon - Dendrites - short, numerous, many branches off cell body : Afferent processes - conduct impulses toward cell body : Can be modified into Sensory Receptors for heat, cold, touch, pressure, stretch, etc - Axon - single process that can be very long, has synaptic knobs at the end - carries signal to another neuron or effector cell (does something when stimulated) - Efferent process - conduct signal away from the cell body Neuroglia - glial cells - structurally and functionally support and protect the neurons -myelin sheath, cell membrane of oligodendrocytes or Schwann cells - Nodes of Ranvier - enhance conduction speed

Which electrolytes are normally more concentrated outside the cell and which ones are more concentrated inside the cell?

Potassium is more concentrated inside the cell, and sodium is more concentrated outside the cell.

List the characteristics of each of the subatomic particles.

Proton - positive charge, atomic mass of 1, grouped in center of atom with neutrons to become atomic nucleus. Protons + neutrons = atomic weight. Atomic number = number of protons Neutron - No charge come atomic mass of one Electron - negative charge, no weight, constantly moving, properties of waves and particles Ion - charged atom, gain or loss of electron Isotope - different number of neutrons Electron shell - 2, 8, 18, 32, 50, 72

Give two examples of conditions that results from fluid shifts.

Pulmonary edema and cutaneous edema are both caused by abnormal shifts in fluid between compartments.

What are the molecular components of rafts & what role do they play in the life of a cell?

Rafts are composed of densely packed phospholipids, cholesterol, and protein. These dense regions are stiff and form rigid, raftlike structures within the otherwise fluid phospholipid bilayer of the cell membrane.

What are the components of areolar tissue?

Randomly placed fibers and cells suspended in a thick, translucent ground substance. The tissue appears relaxed, with a myriad of round and star-shaped cells placed among crisscrossing fibers. The predominant cell is the fibroblast, a large spindle-shaped cell that manufactures the elastic, reticular, and collagenous fibers found throughout the tissue.

Differentiate between yellow and red bone move

Red - hematopoietic (forms blood cells) Majority of bone marrow in young animals but a small portion of older animals (ends of long bones, interiors of pelvic bones and sternum) Yellow - primarily adipose connective tissue (fat). Most common type in adults. Does not produce blood cells but can revert back to red bone marrow if needed

Differentiate between the study of regional anatomy and the study of systemic anatomy.

Regional anatomy - a method of studying anatomy that examines all the component structures that make up each region of the body. For example, the regional approach to abdominal anatomy would examine all the cells, tissues, organs, muscles, blood vessels, and nerves that are present in the abdomen. Systemic anatomy - is a method of studying anatomy that examines each system of the body (e.g., skeletal system, reproductive system) as a separate topic.

How does relaxin help prepare a pregnant animal for parturition?

Relaxin causes ligaments between the bones surrounding the birth canal to soften and relax, facilitating the passage of the newborn during parturition.

Which layer of the eyeball contains the photoreceptors?

Retina (the inner nervous layer)

Describe the structure of the ribs and sternum

Ribs - flat bones that form the lateral wall of the thorax chest. Number of pairs of ribs usually equals number of the rasic vertebrae Dorsal part = bony; head, neck and body Ventral = cartilage; joins sternum or costal cartilage ahead of them - costal cartilage Sternum - breastbone, forms floor of thorax; consists of rod-like bones called Sternebrae 1st = manubrium last = xiphoid process

If you are facing a cat head-on, is its left ear on your left or right side?

Right side.

What kind of vision to the rods in the retina perceive? What do cones perceive?

Rods are more sensitive to light than cones, but they produce a somewhat coarse image in shades of gray. The cones are more sensitive to color and detail than are the rods, but they do not function well in dim light. So rods are the main receptors for dim light vision, and cones perceive color and detail.

How would the rupture or perforation of an ear drum affect hearing?

Rupture or perforation of an eardrum would decrease the tension of the structure. This would decrease the force of the vibrations that move along the ossicles to the inner ear, impairing hearing.

Described each of the 3 types of muscle

SKELETAL Long bundled cells, multiple nuclei, straighted, voluntary Function - voluntary movement of the body Location - attached to bone SMOOTH Spindle shaped cells, single nuclei common non straighted, involuntary Function - moves food and fluid, contracts uterus, makes hair stand erect, regulates organ size Location - in the walls of hollow organs: stomach, blood vessels, uterus CARDIAC Small branch cells, single nuclei, striated, involuntary Function - pumps blood through the vascular system Location - heart

Describe the microscopic anatomy of skeletal muscle, smooth muscle, and cardiac muscle cells

SKELETAL - Long and thin, can be several inches long. usually called fibers instead of cells - Multiple nuclei per cell, located at the edge of the cell - One skeletal muscle fiber = hundreds or thousands of myofibrils = thousands of protein filaments - lots of mitochondria, extensive networks of sarcoplasmic reticulum (storage for calcium ions), and transverse or T-tubules that extend in from the sarcolemma (cell membrane) - The protein filaments form the contractile unit of the myofibril. Each contractile unit is call a SARCOMERE and is the basic contracting unit of skeletal muscle - Z line or Z disc = where sarcomeres meet - Actin = thin protein filaments, attach at z line and extend toward center but don't meet - Myosin = thick protein filaments, float in middle between parallel actin fibers. don't connect to Z lines - I Bands = light colored bands, thin actin filaments, with Z line in middle - A bands = darker bands, where actin and myosin overlap - H Bands = light colored area in the middle of the A band, with only myosin filaments. No overlapping actin filaments - Myosin and Actin interact to shorten the sarcomere during contraction. SMOOTH - Small, spindle shaped (tapered at the ends) with a single nucleus in the center. - Smooth, homogeneous appearance under the microscope because their filaments of actin and myosin are not arranged in parallel myofibrils as in skeletal and cardiac - Small contractile units of actin and myosin filaments crisscross the cell at various angles and are attached at both ends to dense bodies that correspond to the Z lines of skeletal muscles. - When they shorten they cause the cell to ball up as it contracts. Because their contractile units are not organized into regular, parallel sarcomeres, they can shorten more than skeletal or cardiac CARDIAC - Striated like skeletal muscle cells and contain many of the same organelles and intracellular structures such as myofibrils - Much smaller than skeletal muscle cells and have only one nucleus per cell - Longer than they are wide and often have multiple branches - Securely attached to each other end to end to form intricate branching networks of cells. These attachments are visible under the microscope as dark, transverse lines between the cells and are called INTERCALATED DISCS - The intercalated disks securely fasten the cells together and transmit impulses from cell to cell to allow large groups of cardiac muscle cells to contract in a coordinated manner

8-3 Describe a skeletal muscle cell in terms of cell size, shape, number of nuclei, and appearance under the microscope

Skeletal muscle cells are large and long and have multiple nuclei. Under a microscope the cells appear striated or striped.

What are the main differences in the structures and functions of skeletal muscle, cardiac muscle, and smooth muscle?

Skeletal muscle is composed of long, multinucleated cells that are under conscious control. They are striated when viewed microscopically. They move the bones that move the animal's body. Cardiac muscle is found only in the heart. It is made up of striated muscle cells that are not under conscious control. The cells have only one nucleus each. Intercalated discs join cardiac muscle cells end to end. Smooth muscle cells are nonstriated and have a single nucleus. They are not under conscious control. They are found in the walls of internal organs and locations, such as the eye, where delicate movements are necessary.

Differentiate between superficial and central temperature sensors

Superficial temperature receptors are located in the skin and detect upward or downward changes in skin temperature Central temperature receptors keep track of the core temperature of the body by monitoring the temperature of the blood - Receptors are located in the hypothalamus - Rectal temperature indicates core temperature

Differentiate between the sympathetic and parasympathetic divisions of the autonomic nervous system

Sympathetic - "fight or flight" system - prepares body for physical action - mainly NOREPINEPHRINE neurotransmitters Parasympathetic - "Rest and restore" system - Recharges the body for future activities - Mainly ACETYLCHOLINE neurotransmitters

What is the general effect of sympathetic nervous system stimulation on cardiac muscle? What is the effect of parasympathetic nervous system stimulation?

Sympathetic nerves cause the heart to beat harder and faster. Parasympathetic nerves cause the heart to beat slower and with less force.

With which branch of the autonomic nervous system are the Alpha¹, Beta¹, and Beta² receptors associated? What happens to the body when these particular receptors are simulated?

Sympathetic nervous system. Alpha1-adrenergic receptors typically are found on blood vessels and cause the vasoconstriction of the skin, GI tract, and kidney associated with sympathetic stimulation. The increase in heart rate and force of contraction are the result of stimulation of beta1-adrenergic receptors by catecholamines, and the bronchodilation associated with sympathetic stimulation results from beta2-adrenergic receptor stimulation.

List the components of a neuromuscular Junction and describe the function of each component

Synaptic Space - small gap between end of nerve fibers and the sarcolemma (cell membrane) of muscle fiber Synaptic Vesicles - Tiny sacs in the end of a nerve fiber that contain the chemical neurotransmitter acetylcholine Acetylcholine - neurotransmitter that crosses the synaptic space. binds to receptors on sarcolemma and starts process of muscle fiber contraction. Very short effect. Removed by acetylcholinesterase enzyme Motor unit - describes one nerve fiber and all the muscle fibers it innervates

What is synovial fluid and why is it important to the functioning of a synovial joint?

Synovial fluid is produced by the lining of the joint capsule. It lubricates synovial joints, is transparent, and has the viscosity of a medium-weight motor oil. It can be aspirated and analyzed to help diagnose some disorders.

Where are synovial membranes found? How are they different from other membrane types?

Synovial membranes line the cavities of joints. They are different from other membrane types because they have no epithelium and are composed completely of connective tissue.

Give the general equations for synthesis, decomposition, and exchange reactions.

Synthesis: x+y = xy anabolism (o+o =o²) Decomposition: xy = x+y catabolism (2H²O --> 2H² +O²) Exchange: wx+yz = wy+xz Catabolism, then anabolism (NaHCO³ + HCl --> NaCl + H²O + CO²)

Describe the structure of the taste buds

Taste buds = tiny, rounded structures made up of gustatory (sensory) cells and supporting cells - Majority of taste buds are located on the sides of small, elevated structures called papillae, but some are in the lining of the mouth and throat - Tiny openings on the surface of each taste bud (taste pores) allow dissolved substances to enter the taste bud and contact the sensory receptors. (tiny, hair-like processes that project up into the taste pores) - Nerve impulses are generated, travel to brain and are interpreted as taste - Sweet, sour, salty, bitter

10-3 Which skull bone houses the middle and inner ear structures?

Temporal bone

Describe the structure and function of tendons, aponeuroses, and ligaments

Tendons - tough. fibrous connective tissue bands that connect skeletal muscles to bone Aponeuroses - broad sheets of fibrous connective tissue that attach muscles to bone or muscle (linea alba = most prominent, connects abdominal muscles together) Ligaments - bands of fibrous connective tissue that are present in and around many synovial joints. Similar to tendons but join bone to bone.

What is the difference between a tendon and a ligament?

Tendons join muscles to bones. Ligaments join bones to other bones.

Which hormone are anabolic steroids drugs related to?

Testosterone

3-4 Why do inclusions vary in appearance? What function do they perform?

The appearance of inclusions varies depending on what they contain and whether or not they have an envelope. They store substances the cell eventually uses.

What is a sarcomere and what are its components?

The basic contracting unit of skeletal muscle. It consists of the actin and myosin filaments between Z lines in a muscle cell. Myofibrils are composed of many sarcomeres stacked end to end

What helps keep dangerous poisons and certain drugs from leaving the blood and entering the brain? Described this structure

The blood-brain barrier consists of capillary-wall cells in the brain that are aligned tightly together without openings, or fenestrations. In addition, the capillaries in the brain are covered by the cell membranes of glial cells.

What are the brachium and antebrachium, and which bones form them?

The brachium is the upper forelimb between the elbow and shoulder joints formed by the humerus. The antebrachium is the forelimb formed by the radius and ulna.

What types of protein are found in the cell membrane?

The cell membrane contains structural and globular proteins. Globular proteins include integral and peripheral proteins.

3-2 Name the three structures that all mammalian cells possess.

The cell membrane, the cytoplasm (which includes cytosol and organelles), and the nucleus

9-2What are the anatomic differences between the CNS and the PNS?

The central nervous system (CNS) is composed of the brain and spinal cord, which are found associated within the central axis of the animal's body. Peripheral means "to the side" or "away from the center"; therefore, the peripheral nervous system (PNS) is made up of those components of the nervous system that extend away from the central axis outward toward the periphery of the body.

What is the centrosome and what important roles does it play in the life of the cell?

The centrosome is a critical region in the cytoplasm adjacent to the nucleus. It is the site where microtubules are constructed and demolished. The centrosome includes centrioles, pericentriolar material, and asters. Microtubules are the thickest and strongest fibers in the cell and form the "zip-line"-like cables in the cytoskeleton that transport organelles and other intracellular structures from one place to another inside the cell. They also help form the spindle fibers during cell division and are a central part of cilia and flagella.

The cornea and sclera are both made up substantially of collagen fibers. Why is the cornea transparent, but the sclera opaque?

The cornea contains no blood vessels, and the amount of water it contains is carefully controlled.

What is the main refractive structure of the eye? Why?

The cornea is the main refractive structure because of its curvature and the extreme difference between its optical density and that of the air in front of it.

What is the cytoskeleton and what is its function?

The cytoskeleton is a three-dimensional frame for the cells that is neither rigid nor permanent. It is a flexible, fibrous structure that changes in accordance with the activities of the cell. The cytoskeleton gives support and shape to the cell and enables it to move, provides direction for metabolic activity, and anchors the organelles.

List the components of the dorsal body cavity.

The dorsal body cavity contains the brain and spinal cord, that is, the central nervous system. It consists of two parts; a somewhat spherical cranial cavity in the skull and a long, narrow spinal cavity running down the spine.

7-1 Besides supporting the other tissues of the body, what else to bones do?

• Bones protect many delicate vital organs and tissues by surrounding them partially or completely. • Bones act as levers for the skeletal muscles to move the body. Attachment of skeletal muscles to bones via the tendons allows the muscles to move joints, enabling an animal to move about in its environment. • The bones act as storage sites for minerals, particularly calcium. • Some of the bones serve as sites for blood cell formation (hematopoiesis) in the bone marrow that fills their interiors.

What are the correct names for the bumps and fissures that make the cerebral cortex appear wrinkled?

The folds, called gyri (plural of gyrus), are separated by deep grooves called fissures and more shallow grooves called sulci (plural of sulcus). The most prominent groove is the longitudinal fissure, which divides the cerebrum into right and left cerebral hemispheres.

How might abnormalities in an animal's anatomy or physiology have a negative impact on its health and well-being?

The functions of the parts of an animal's body are extremely interrelated. Therefore an abnormality with the anatomy or physiology of one part can affect other parts.

what is the glycocalyx and what important role does it play in cellular interaction?

The glycocalyx is a "sugar coating" on the outside of the cell; it is made of glycoprotein and glycolipid molecules. Similar to the stripes on zebras or the fingerprints on human hands, each glycocalyx is unique. It provides improved cell-to-cell adhesion and represents an important biologic marker for intercellular recognition and for the interactions between the cell and antibodies and the cell and viruses.

Where are goblet cells found? What type of secretion do they produce?

The goblet cell is a modified columnar epithelial cell found interspersed among the columnar cells of the respiratory and digestive tracts and in the conjunctiva of the eye. Goblet cells secrete mucin, a thick, sticky mixture of glycoproteins and proteoglycans. When combined with water, mucin becomes mucus. The mucus functions in two ways: it helps protect the apical surface of the epithelial layer, and it assists with the entrapment of microorganisms and foreign particles.

How does the normal anatomy and physiology of cells in an animal's body impact the health of the animal as a whole? How does the normal anatomy and physiology of the animal's body as a whole impact the health of its cells?

The health of cells affects the health of tissues, which affects the health of organs, which affects the health of systems, which affects the health of the whole body. Similarly, the health of the body affects the health of the systems, which affects the health of the organs, which affects the health of the tissues, which affects the health of cells.

Draw a picture of the lipid bilayer, which part is hydrophobic and hydrophilic?

The hydrophilic heads of the phospholipid bilayer are attracted to the aqueous environments found in the extracellular and intracellular spaces. The lipid tails, on the other hand, are hydrophobic and are repelled by these aqueous compartments. Therefore, they are turned inward and face one another inside the bilayer.

What is the function of the Iris?

The iris controls the amount of light that enters the posterior part of the eyeball. The pupil enlarges in low light conditions and gets smaller in bright light.

What are the anatomical names for the cannon bone and the splint bones in a horse?

The large metacarpal (cannon) bone of the horse is assumed to be what is left of metacarpal III, and the smaller splint bones on either side of it are designated as metacarpals II and IV.

If your left hand is on a goat's belly and your right hand is on its back, which hand is on the animal's dorsal surface and which is on its ventral surface?

The left hand is on the ventral surface, and the right hand is on the dorsal surface.

What is the manubrium?

The manubrium is the first, most cranial, sternebra.

The next time you see a dog, differentiate between the medial and lateral surfaces of one of its elbows and the proximal and distal ends of one of its legs.

The medial surface is toward the center line of the animal's body, and the lateral surface is on the outer side of the elbow. the proximal part of the leg is closer to the body relative to, for example, the toes, which are located distally.

9-6 What are the protective membranes that surround, support, and protect the CNS?

The meninges. These are a set of connective tissue layers that surround the brain and spinal cord. The three layers of the meninges, from outside to innermost layer, are the tough, fibrous dura mater, the delicate, spider web-like arachnoid, and the very thin pia mater, which lies directly on the surface of the brain and spinal cord.

How does each of these organelles function within the cell?

The mitochondrion produces 95% of the energy that fuels cellular activity. The energy is predominantly stored in the terminal phosphate bond of adenosine triphosphate (ATP) molecules. The ATP is derived from an array of biochemical processes using oxygen and nutrient molecules. Oxygen enters the body via respiration, and nutrient molecules are provided from food sources. Remarkably, mitochondria contain their own DNA, which includes the instructions for making the enzymes used to make ATP. The ribosome is the site of protein synthesis. Soluble protein intended for intracellular use is manufactured on free-floating ribosomes found throughout the cytosol, whereas protein intended for export outside the cell is synthesized on fixed ribosomes found on the rough endoplasmic reticulum (RER). Newly manufactured molecules of protein are moved internally into passageways in the RER known as cisternae, Latin for "reservoirs." Here the proteins are modified before being moved on to the Golgi apparatus for further modification and packaging. The membrane of the RER is an extension of the outer nuclear membrane, so that RER is often found near the nucleus. Smooth ER, which is connected to rough ER, is active in the synthesis and storage of lipids, particularly phospholipids and steroids, and is therefore seen in large quantities in gland cells. In liver cells smooth ER may also function to eliminate drugs and break down glycogen into glucose. The Golgi apparatus acts as a modification, packaging, and distribution center for molecules destined for either secretion or intracellular use. It also functions in polysaccharide synthesis and in the coupling of polysaccharides to proteins (glycoproteins) on the cell surface. The lysosome's principal responsibilities are the breakdown of nutrient molecules into usable smaller units and the digestion of intracellular debris. Lysosomes may also release their enzymes outside the cell to assist with the breakdown of extracellular material. In addition, lysosomal digestion is responsible for decreasing the size of body tissues (for example, shrinkage of the uterus after parturition and atrophy of muscles in paralyzed animals). Peroxisomes are commonly found in liver and kidney cells and are important in the detoxification of various molecules. Peroxisomes contain enzymes that use oxygen to detoxify a number of harmful substances, including alcohol and formaldehyde. They also assist in the removal of free radicals, which are normal products of cellular metabolism that can be harmful to the cell in large quantities because they interfere with the structures of proteins, lipids, and nucleic acids. Proteasomes are minute structures that consume individual, often misfolded proteins and digest them. They are found throughout the cytosol. Vaults are tiny, hollow transport complexes that are thought to attach to fibers in the cytoskeleton that enable rapid movement from one part of the cell to another. Vaults are able to open up and may lock into nuclear pore complexes on the nucleus, where they may pick up and drop off molecules.

What is the most important function of neural tissue?

The most important function of neural tissue is to receive and transmit electrical and chemical signals throughout the body.

4-2 When is a membrane process considered active?

The movement of molecules and substances across the cell membrane is considered active when the process requires energy. Energy is stored in molecules such as adenosine triphosphate (ATP). Removal of the terminal phosphate in ATP releases the stored energy needed to drive an active membrane process.

Explain why waves of depolarization are conducted faster in myelonated axons than in unmyelinated ones

The myelin sheath prevents sodium ions from flowing across the neuronal cell membrane. Therefore, depolarization in myelinated axons can only take place at the gaps in the myelin sheath that occur at the nodes of Ranvier. When the sodium influx at one node is sufficient to open adjacent sodium channels, the next available sodium channel is at the next node of Ranvier. The depolarization wave in the myelinated axon skips from one node of Ranvier to the next, greatly accelerating the rate at which the depolarization wave moves from the neuron cell body to the other end of the axon.

Describe the effect of a cardiac muscle's nerve supply on its functioning

The nerve supply to cardiac muscle does not initiate cardiac muscle cell contraction but it can modify the contraction.

9-1 How do basic communication and control functions differ between the nervous system and the endocrine system

The nervous system's chemical messengers, neurotransmitters, are contained in nerve endings. They are released across the small synaptic space when nerve impulses reach the nerve ending. This allows the nervous system to react quickly to changes, but neurons (nerve cells) cannot sustain individual activities for long periods of time. The endocrine system's chemical messengers, hormones, are released into the bloodstream, where they travel to their target cells. This causes the endocrine system to react more slowly to changes, but it can sustain individual activities for long periods of time.

On which bone is the olecranon process found? What is its purpose?

The olecranon process forms the point of the elbow and is on the ulna. It is the site where the tendon of the powerful triceps brachii muscle attaches.

Why is the optic disc the blind spot of the eye?

The optic disc contains only nerve fibers and a few blood vessels but no photoreceptor cells, so no visual images are formed there.

What is the origin of a muscle? The insertion?

The origin of a muscle is the most stable attachment site. The insertion of a muscle is the site that undergoes the most movement when a muscle contracts.

What surface of a hamster's front leg is in contact with the ground when it is walking normally? What surface of the hind leg?

The palmar surface of the front leg and the plantar surface of the hind leg are touching the ground.

What is the palpebral reflex? How is it used in veterinary medicine?

The palpebral reflex arc originates from receptors on the eyelid margins, travels via sensory neurons in CN V to the pons (brain stem), synapses with neurons in the pons, and then travels via CN VII to the muscles that blink the eyelids. If the reflex is active, a light tap on the medial canthus of the eye (the medial corner of the eye where the top and bottom eyelids meet) produces a blink of the eyelids. When an animal is anesthetized, the neurons in the pons become less responsive. Therefore, as anesthesia deepens, the palpebral reflex (also called the palpebral blink reflex) becomes less responsive and provides an indication of the animal's depth of anesthesia.

What normally maintains the resting membrane potential of a neuron during the resting state?

The resting membrane potential is maintained by the distribution of positive and negative charges from sodium, potassium, proteins, and other charged ions on either side of the neuronal membrane, creating a difference in electrical charge across the membrane, with the inside of the neuron being more negatively charged than the outside. By selectively pumping sodium out and potassium in, the sodium-potassium pump maintains this negatively charged resting membrane potential.

How does each of the anatomic planes of reference (sagittal, median, transverse, and dorsal) divide a cow's body?

The sagittal plane divides the body into left and right parts, which are not necessarily equal. The median plane divides it into equal left and right halves. The transverse plane divides the body into cranial and caudal parts, which are not necessarily equal. The dorsal plane divides the animal's body at a right angle to the sagittal or transverse plane and divides the body into dorsal and ventral parts, which are not necessarily equal.

9-3 During depolarization, what ion channels open and what ion moves? Where does it move?

The sodium channels open and sodium ions move into the cell.

Which bone is larger and supports more of an animal's weight, the tibia or the fibula?

Tibia

Differentiate among the 3 major types of cellular junctions found between epithelial cells

Tight junctions - fusion of adjacent cells plasma membrane, where leakage must be prevented (Bladder, digestive tract). Substances have to pass through the cell Desmosome - strong plaque connects plasma membranes of adjacent cells, in areas that undergo tension and stretching. Formed by filaments that interlock like Velcro. (Skin, heart, uterus) - Tonofilaments - extend into cytoplasm like anchors. - Hemidesmosomes - half of a desmosome, link to basement membranes Gap Junction - linked by tubular channel proteins called connexons, extend from cytoplasm to cytoplasm. Allow exchange of ions and nutrients. (Intestinal epithelium, heart, smooth muscle tissue)

Why does an animal breathe heavily for a while after heavy exercise?

To replace the amount of oxygen that is used to convert lactic acid to glucose in the liver

Describe the process of inflammation. What causes the clinical signs of heat, swelling, redness, and tenderness?

To sum up the sources of the clinical signs accompanying inflammation: Heat and redness are caused by increased blood flow to the area. Swelling is caused by fluid from plasma, composed of enzymes, antibodies, and proteins, pouring into the affected area. This swelling irritates delicate nerve endings and causes pain and tenderness in the affected area. Inflammation begins with a 5- to 10-minute period of vasoconstriction followed by a sustained period of vasodilation. The initial constriction occurs in the small vessels of the injured tissue and aids in the control of hemorrhaging. Histamine and heparin molecules released from mast cells stimulate vasodilation and increase permeability of capillaries. Blood flow to the area is increased, which in turn causes the clinical signs of heat and redness. Blood flow also increases the supplies of oxygen and nutrients to the active cells of the damaged tissue. Plasma fluid, composed of enzymes, antibodies, and proteins, pours into the affected area, causing swelling of the soft tissue structures. This swelling irritates delicate nerve endings and causes pain and tenderness in the affected area. Clot formation begins to take place, which slows bleeding. The clot also helps isolate the wound from the invasion of pathogens and helps prevent bacteria and toxins from spreading to surrounding soft tissue structures. A clot first forms when platelets become sticky and clump together. Fibrinogen, found in rich quantities in the swollen tissue, is converted to an insoluble protein called fibrin. Fibrin is woven into a netlike structure that surrounds the platelets and provides support and stability to the newly formed clot. It also forms a framework to support the movement of cells throughout the site. Clots that form on the skin eventually dry and become known as scabs. Large cells, such as macrophages and neutrophils (types of white blood cells), move through blood vessels and can squeeze through dilated capillaries to assist in the removal of debris and microinvaders. The phagocytic cells are short lived, however, and can function for only a few hours before dying. Pus, which is an accumulation of dead and degenerated neutrophils and macrophages, may therefore collect in the injured area. With increased blood flow, histamine and heparin are dispersed, and their levels drop in the affected area. The decrease in these molecules causes the return of normal capillary size and permeability. When capillaries return to normal size, blood flow and fluid leakage into the affected area abate. Swelling, heat, and redness begin to subside.

Why do touch and pressure sensations fade so rapidly from the conscious mind unless they change or are severe?

Touch and pressure sensations are not threats to the well-being of the animal and tend to fade from the conscious mind, allowing the CNS to focus on other more important sensations.

Which layer of the eyeball are the Iris and ciliary body part of?

Uvea

Describe the processes that contribute to the sense of equilibrium

VESTIBULE - The portion of the inner ear that is located between the cochlea and the semicircular canals - UTRICLE and SACCULE - To sac-like spaces that are continuous with the cochlear duct of the cochlea and are filled with the same Endolymph fluid. Surrounded by Perilymph MACULA - A patch of sensory epithelium in each utricle and saccule. Consists of hair cells and supporting cells covered by a gelatinous matrix that contains tiny crystals of calcium carbonate called otoliths OTOLITHS - Tiny crystals of calcium carbonate, in gelatin - Gravity causes the otoliths and the gelatinous matrix to put constant pressure on the hairs as long as the head stays still. Movement of the head bends the sensory hairs, which generates nerve impulses that give the brain information about the position of the head SEMICIRCULAR CANALS Located on the other side of the vestibule from the Coke via. Each canal is semi circular and oriented in a different plane at right angles to the other two. Like a corner of the ceiling where 2 walls and the ceiling come together. AMPULLA - In enlargements near the utricle end of each semicircular canal, contains the Crista CRISTA AMPULLARIS (or just CRISTA) - Similar to the macula of the vestibule. Consists of a cone shaped area of supporting cells and hair cells with their processes sticking up into a gelatinous structure called the cupula. But there are no otoliths to weigh it down, it functions as a float that moves with the endolymph in the membranous canal. CUPULA - a cone shaped gelatinous structure that sits on top of the receptor hairs in the crista of the semicircular canals

Differentiate between visceral smooth muscle and multi-unit smooth muscle

VISCERAL SMOOTH: - Found in the walls of many internal soft organs - large and powerful - Fine movement is not possible - large, rhythmic contracting - No need for external stimulation (but reacts to stretching) - Nerve supply that is not necessary but modifies it (sympathetic and parasympathetic) MULTI-UNIT: - Small and delicate, made up of individual smooth muscle cells or small groups of cells - Not automatic, require specific autonomic nerve impulses - Specific and carefully controlled, found where small, delicate contractions are needed - Iris, ciliary body of eye, walls of small blood vessels, small air passageways in lungs

Where in a vertebra is the spinal cord located?

Vertebral foramen formed by the vertebral arch and the vertebral body

10-1 Why are visceral sensations important to the survival of an animal?

Visceral sensations keep the CNS informed about the overall prevailing conditions inside and outside the body. The result is the initiation of behaviors designed to ensure the well-being of the animal.

List the divisions of the spinal column

cervical - neck region thoracic - thoracic (chest) region lumbar - abdominal region sacral - pelvis region coccygeal - tail

What are the main differences between visceral smooth muscle and multi-unit smooth muscle?

Visceral smooth muscle is found in the walls of internal soft organs (viscera). The muscle cells are linked to form large sheets. Fine movement is not possible because the contractions are strong. Multiunit smooth muscles are small and delicate. They are made up of individual cells or small groups of cells. They are found where small, delicate contractions are needed.

Why do changes in osmolality cause fluid to move from one compartment to another?

Water moves freely between fluid compartments based on changes in osmolality of the fluid in each compartment. Fluid moves toward the compartment with the highest concentration of solutes, and therefore the highest osmolality.

Matthias Schleiden

german botanist concluded that all plants were made of cells in 1838

Theodor Schwann

german zoologist concluded that all animals were made of cells in 1839

Describe the effects of growth hormone, prolactin, thyroid-stimulating hormone, adrenocorticotropic hormone, follicle-stimulating hormone, luteinizing hormone, melanocyte-stimulating hormone, antidiuretic hormone, and oxytocin

growth hormone - prolactin - thyroid-stimulating hormone - adrenocorticotropic hormone - follicle-stimulating hormone - luteinizing hormone - melanocyte-stimulating hormone - antidiuretic hormone - oxytocin -

7-4 Which groups of vertebrae make up the spinal column dorsal to the following regions? Abdomen Neck Pelvis Tail Thorax

• Abdomen: lumbar • Neck: cervical • Pelvis: sacral • Tail: coccygeal • Thorax: thoracic

cell layers of retina

rods and cones

List and describe the special senses

sense. sensed. type of stimulus Taste. tastes chemical Smell. odors. chemical Hearing sounds. mechanical Equilibrium. balance and head position. mechanical Vision. light. electromagnetic

List the steps in replication of DNA

1. In the nucleoplasm of a cell, chromosomes uncoil from their superhelical and helical formations to form loose strands of chromatin (DNA and histone proteins) 2. The portion of DNA to be copied and wraps and separates from the histone proteins 3. A special protein, called a helicase enzyme, initiates the untwisting of the DNA helix and separates portions of the DNA into 2 nucleotide chains. Each region along the long strand where the DNA has separated is called a replication bubble. The spot at which the bubble begins and ends is called a replication fork 4. Free DNA nucleotides, which are dissolved in the surrounding nucleoplasm, are attracted to the exposed complementary nucleotide. These molecules pair to one another in complements. Remember that the purines, adenine and guanine, always bond to the pyrimidines, thymine and cytosine, respectively. Thus, the original DNA strand is a template for the formation of a complimentary new strand. If the original strand reads GATTAG, the complimentary new strand will read CTAATC 5. DNA replication is carried out by a molecular machine called a replisome. The replisome is compose of a collection of proteins including 2 types of enzymes called primases and replicases 6. Interestingly, the replication process begins when the primases attach a short chain of RNA to the DNA template strand. These RNA primers are about 10 bases long 7. Once the RNA primer is in place, DNA replication can begin in earnest. An enzyme called dna polymerase 3 places complimentary nucleotide along the template strand and covalently links them together. In this way, polymerase 3 is responsible for assembling the majority of the new nucleotide strand 8. DNA polymerase 3 moves only in one direction, so the 1st strand, the lead strand, is made continuously while the 2nd strand, the lagging strand, is made in segments and subsequently joined together by an enzyme called DNA ligase. When DNA polymerase 3 has finished building a new strand, DNA polymerase 1 moves in and replaces the RNA primer with DNA nucleotides 9. Finishing touches are added. Telomeres, nucleoprotein caps, are placed on the ends of each DNA strand to protect the ends from damage. In addition, histone proteins are imported into the nucleus from the cytoplasm, and DNA is wrapped around them, forming chains of nucleosomes 10. The identical DNA strands become chromatids, joined together at a central point called the centromere. Each chromatid is an exact replica of the other, each containing one strand of the original DNA molecule and 1 strand of the new compliment

Why is water called a polar molecule?

1. It has a slight positive charge in the area of the hydrogen atoms and a slight negative charge in the area of the oxygen atom. This polarity allows water molecules to form hydrogen bonds with each other and with other polar molecules.

List the cell types that comprise the epidermis and describe the function of each cell type

1. Keratinocytes - Primary cell type in epidermis Produces keratin (tough, waterproofing protein) 2. Melanocytes - found in basal layer of epidermis - Produce dark pigment called melanin (stored in granules called melanosomes) - Melanosomes are released into interstitial space, absorbed by keratinocytes on superficial side in response to UV light 3. Langerhans cells - Macrophage specific to the epidermis - Originates in bone marrow, migrates to skin - Phagocytizes microinvaders, plays important role in helping to stimulate other aspects of the immune system 4. Merkel cells - Located at the epidermal-dermal junction - Small numbers - Associated with sensory nerve endings and may aid in sensation of touch - Has half dome shape to pair with half dome sensory nerve ending (together called Merkel Disk)

Describe the process of keratinization

1. Keratinocytes along basement membrane are actively dividing 2. Daughter cells are pushed up to the skin surface away from blood supply 3. Cells die is they move to surface - Fill with keratohyaline granules - Lose nuclei, cytosol, and organelles - Become lifeless sheets of keratin 4. New epidermis forms within 2 months

List the 4 general types of stimulus that can trigger a response from sensory receptors

1. Mechanical stimuli (touch, hearing, and balance) 2. Thermal stimuli (hot and cold) 3. Electromagnetic stimuli (vision) 4. Chemical stimuli (taste and smell)

Describe the structure and functions of each of the cellular organelles, inclusions, and vesicles. Then draw a diagram of each. Why do inclusions vary in appearance?

1. Mitochondria: Double membrane bound organelle, internal membrane folds inward forming cristae; increased internal surface area maximizes metabolic processes. Site of cellular respiration, which produces ATP. 2. Endoplasmic reticulum: A system of collapsed sacs extending from the outer layer of the nuclear envelope. Has two forms: rough with ribosomes, and smooth without ribosomes. Rough ER produces, modifies, and packages Proteins. Smooth ER produces, modifies and packages Lipids and Carbohydrates. 3. Ribosome: 2 subunits, fit like cupped hands. Each is made of RNA and protein. Fixed ribosomes on RER, free float in cytosol. Site of protein synthesis. Fixed make proteins for export, free floating make proteins for intracellular use. Ribosomal subunits are made in the nucleoli. 4. Proteasome: Hollow cylinder composed of subunits and caps on each end. Breaks down individual misfolded or abnormal proteins. Found throughout cytosol. 5. Golgi apparatus: Network of connected flat tubes stacked on top of one another (pancakes). Refines and alters molecules for secretion and internal use. Produces lysosomes. 6. Lysosomes: Vesicle filled with hydrolytic enzymes, formed by golgi apparatus. Digestion of absorbed material and internally produced waste. Rupture causes cellular autolysis. 7. Peroxisomes: Membrane bound vesicle containing enzymes: produced by fission. Detoxify various molecules such as alcohol and formaldehyde; removes free radicals 8. Vaults: Tiny, barrel-shaped capsule composed of RNA and protein. Thought to be very numerous in cells. Perhaps able to fit into nuclear pore complexes where one end opens to pick up or drop off molecules entering or exiting the nucleus 9. Inclusions: Vesicles, vacuoles and lipid droplets suspended in cytosol. Storage and transportation vesicles of intracellular substances 10. Cytoskeleton: Structural complex within cytosol composed of microtubules, intermediate filaments, and microfilaments. Provides strength, structure, and support; maintains cell shape, and affects cell division, and movement of organelles and the cell membrane 11. Centrioles: Found in the center of the centrosome near the nucleus. Composed of microtubules arranged in a pin-wheel. Asters radiate away from the centrioles. Duplicate prior to cell division. Moher and daughter centrioles. Help anchor spindle fibers. Two pairs of centrioles move apart as the spindle fibers lengthen.

Describe factors that determine whether a molecule can pass through the plasma membrane by passive fusion.

1. Molecular size: gases and small molecules diffuse in-and-out easily 2. Lipid solubility: lipid soluble molecules (alcohol and steroids) can pass through cell membrane 3. Molecular charge: ions can not pass without channel proteins Water (small), 0² and CO² (gases), chloride and urea (channels) passively diffuse

What is a molecule?

1. Molecules are atoms joined together by chemical bonds.

What element is found in all proteins that are not found in carbohydrates or lipids?

1. Nitrogen

What are the 3 kinds of bone cell? What role does each play in the life of a bone?

1. Osteoblasts are the cells that form bone where it is needed. They secrete the matrix of bone and then supply the minerals necessary to ossify (harden) it. Once the osteoblasts become trapped in the ossified matrix they have created, they are called osteocytes. 2. Osteocytes are bone cells. 3. Osteoclasts eat bone away. Bones are dynamic structures that must be remodeled constantly. By removing bone from where it is not needed, osteoclasts make it possible for remodeling to take place. They also allow the body to withdraw calcium from the bones when it is needed to raise the calcium level in the blood.

Test Yourself 6-2 What causes pigmentation of the skin?

1. Pigmentation is caused by the presence or absence of melanin granules in the armlike extensions of the melanocytes. Macroscopically, no pigmentation is apparent if the granules are concentrated around the nucleus in the cell body of the melanocyte. As the granules move into the cellular arms and into the surrounding tissue, however, pigmentation becomes apparent. The more granules that exist in the arms of the melanocyte and surrounding tissue, the darker the pigmentation. The dispersion of granules is controlled by the release of melanocyte-stimulating hormone, which, in turn, is controlled by the intermediate lobe of the hypophysis. The melanosomes are transported to the tips of the cellular projections, where they are released into the intracellular space and ultimately absorbed by keratinocytes, which arrange the melanin on the side of the cell with the greatest amount of sun exposure. In this way, pigment acts to protect cells from the damaging effects of ultraviolet rays.

List and describe the characteristics used to classify different glands

1. Presence or absence of ducts (endocrine or exocrine) 2. Number of cells that compose them (unicellular or multicellular) 3. Shape of the secreting duct (simple or compound) 4. Complexity of the glandular structure (tubular, acinar, or tubuloacinar) acinar = alveolar 5. Manner in which the secretion is stored and discharged (merocrine (releases), apocrine (loses top), holocrine (cells dies) 6. Type of secretion they produce (mucoid or serous)

What happens in each of these mitotic stages (Prophase, Metaphase, Anaphase, Telophase)?

1. Prophase: Chromatin coils and condenses into chromosomes that are visible with light microscopy. These chromosomes are composed of two identical chromatids linked together at a constriction in their middle known as the centromere or kinetochore. The cytoplasm becomes more viscous as microtubules from the cytoskeleton are disassembled and the cell becomes round. Two pairs of centrioles form anchors on which new microtubules are constructed, and as the microtubules lengthen, they push the centrioles farther and farther apart. In this way a mitotic spindle is formed that provides the structure and machinery necessary to separate the chromosomes. Because transcription and protein synthesis cannot occur while the DNA is tightly coiled, the appearance of chromosomes marks the cessation of normal synthetic processes. Prophase is thought to conclude with the disintegration of the nuclear envelope. 2. Metaphase: Chromosomes line up in the exact center of the spindle, known as the equator. The chromosomes are evenly spread apart and form what is called the metaphase plate midway between the poles of the cell. The centromere of each chromosome is attached to a single spindle fiber. 3. Anaphase: The centromeres of the chromosomes split apart and each chromatid becomes its own chromosome. The spindle fiber separates, each spindle segment shortens, and the twin chromosomes are pulled away from each another. The chromosomes take on a V shape as they are dragged at their midpoint toward the centrioles at opposite ends of the cell. The cell becomes elongated, and the cytoplasm begins to constrict along the plane of the metaphase plate. Although anaphase is the shortest phase of mitosis and usually lasts only a few minutes, its importance is clear in light of the devastating consequences if an error were to occur in chromosome separation. In anaphase the advantage of separating compact bodies of chromosomes, rather than long thin threads of chromatin, is particularly obvious. 4. Telophase: Begins when chromosomal movement stops. The chromosomes, having reached the poles, begin to unravel, elongate, and return to a diffuse threadlike form (chromatin). A nuclear envelope appears around each new set of chromosomes, and nucleoli appear in each nucleus. The microtubules that made up the spindle in the earlier phases of mitosis disassemble, and a ring of peripheral microfilaments begins to squeeze the cell into two parts. Ultimately, the cell pinches itself in half, dividing the cytoplasm and forming two completely separate daughter cells. The process of cytoplasmic division is called cytokinesis and marks the end of telophase.

Describe the functions of epithelial tissues

1. Protects, covers and lines - bladder, mouth, blood vessels 2. Filters biochemical substances - skin, prevents entrance 3. Absorbs nutrients - GI tract, absorbs nutrient molecules 4. Provide sensory input - cells in tongue are sensitive to touch, temperature and taste 5. Manufactures secretions - goblet cells secrete mucus into intestines 6. Manufactures excretions - sweat is excreted by glandular epithelia

List the 5 layers of the epidermis

1. Stratum germinativum (Basal Layer) - Deepest layer: Single row of keratinocytes attached to the basement membrane, actively dividing 2. Stratum spinosum (spiny layer) - Contains several layers of keratinocytes that are held together by desmosomes - resemble sea urchins, also called prickle cells - infrequent divisions - langerhans cells (phagocytic cells) found in great abundance 3. Stratum granulosum (granular layer) - Middle layer; 2 to 4 layers of flattened keratinocytes - cell dies quickly 4. Stratum lucidum (clear layer) - Only in very thick skin - Dead cells 5. Stratum corners (horny layer) - Outermost layer - 20 to 30 rows of keratinocytes

Describe the role of ions in maintaining a cell' resting membrane potential.

1. The difference in permeability of charged particles along the cell membrane leads to variations in the amount, type, and distribution of ions (K+, Na+) on either side of the cell membrane. 2. These variations form a membrane potential or voltage 3. Voltage is potential electrical energy created by the separation of opposite charges 4. All cells maintain a potential of -20 to -200 million volts (negative inside cell) Resting membrane potential -electrical charge of cells at rest due to differing ion concentrations in and out of cell membranes

6-3 Draw and label the parts of a hair follicle

1. The labeled drawing should show hair bulb, papilla, and matrix.

List four types of cellular Junction. Can you describe them?

1. Tight junction: formed by the fusion of the outermost layers of the plasma membranes of adjoining cells. The matrix-filled space between cells is lost at the site of a tight junction. For centrally placed cells, the fusion occurs as a strip that wraps around the entire circumference of the cell like a belt. In this way, an impenetrable barrier is formed that prevents the passage of substances from the luminal end to the basal end of the cell and vice versa. Only by passing through the body of the cell can substances pass through the epithelial layer. Tight junctions are found in tissues in which there can be no leaks—for example, in the urinary bladder, where urine is held, or in the digestive tract, where tight junctions play a critical role in preventing the leakage of digestive enzymes into the bloodstream. 2. Desmosome: strong, welded plaque that connects the plasma membranes of adjacent cells. The bond is a mechanical coupling formed by filaments that interlock with one another, just as plastic fibers do in Velcro. Tonofilaments, or intermediate filaments, may also extend from the desmosomic plaque into the cytoplasm of each cell like anchors, forming stabilizing bases for the membrane junction. In this way, desmosomes form tough bonds between cells and therefore are found most commonly in tissues that undergo repeated episodes of tension and stretching, such as the skin, heart, and uterus. 3. Hemidesmosome: junctions that look like half-desmosomes and link epithelial cells to the basement membrane. 4. Gap junction: made of tubular channel proteins called connexons and extends from the cytoplasm of one cell to the cytoplasm of another. These transmembrane proteins allow the exchange and passage of ions and nutrients (e.g., nucleotides, sugars, and amino acids) from one cell to another. Gap junctions are most commonly found in intestinal epithelial cells, the heart, and smooth muscle tissue. The function of gap junctions in epithelial cells is not yet fully understood, but their ability to quickly transport electrical signals from one cell to another explains their presence in cardiac and smooth muscle cells, where they help coordinate contraction.

Test Yourself 6-4 Name 2 types of sweat glands. How are they different from one another?

1. Two types of sweat glands are eccrine and apocrine. The excretory portion of the eccrine gland consists of a simple coiled tube located in the dermis or hypodermis and connected to the surface of the skin by a long duct. In dogs, eccrine sweat glands are found only in the deep layers of the fat and connective tissue of footpads. Like eccrine sweat glands, apocrine sweat glands have a coiled excretory portion buried in the dermis or hypodermis with a single excretory duct. However, unlike eccrine sweat glands, apocrine glands empty into hair follicles rather than onto the surface of the skin. In the dog, apocrine glands are located in the external ear canal.

List the unique properties of the water molecule

1. Universal solvent ( More chemicals can be dissolved in water than any other known solvent) 2. Ideal transport medium in living systems (blood, urine) 3. High heat capacity and high heat of vaporization - able to absorb heat from biochemical reactions so overall temperature of water stays stable and changes slowly - needs a high temperature to change to steam 4. Used for lubrication (pericardial sac (reduces friction), joint fluid)

What is keratinization and why is it an important process?

2. The majority of cells in the epidermis are keratinocytes. Keratinocytes located along the basement membrane are well nourished by the blood supply of the underlying dermis; therefore, these cells can grow and divide. When new daughter cells are produced, they push older cells away from the life-sustaining nutrients of the dermis toward the outer layers of the epidermis. As older cells travel from the basal to the superficial layers, they undergo profound changes: they fill with keratohyalin granules; lose their nuclei, cytosol, and organelles; and ultimately become lifeless sheets of keratin. This process is called keratinization and enables millions of dead cells to rub off or "exfoliate" daily at nterm-0o expense to the animal's health. Keratinization is important because keratin is a tough, fibrous, waterproof protein that gives skin its resiliency and strength.

What does pH mean?

2. The pH of a solution is a measure of its acidity or alkalinity.

How does hair form and grow?

2. The part of hair visible above the skin is called the shaft, and the portion buried within the skin is called the root. A web of sensory nerve endings called the root hair plexus envelops the root, making it an important touch receptor when the hair is bent. Hair is anchored by the hair follicle. The follicle is an invagination of the epidermis that extends from the skin surface to the dermis or, occasionally, the hypodermis. The deepest part of the hair follicle expands to form a hair bulb. At the base of the bulb is a mound of dermal cells called the papilla. The papilla is covered with rapidly dividing epithelial cells called the matrix. These cells are nourished by blood flow from vessels in the underlying papilla, which stimulates much cell division and growth. As cells divide, older cells are pushed upward into the follicle tunnel away from the papilla. These cells become keratinized, and as they lose contact with the nutrition provided by the papilla, they die and become part of the developing hair. In this way, hair is constructed from dead epithelial cells. The wall of a hair follicle is composed of three layers: an internal epithelial root sheath, an outer epithelial root sheath, and a dermal or connective tissue root sheath. Animals with fur often have compound follicles in which multiple hair strands emerge from a single epidermal orifice, or pore, although each strand has its own follicle and bulb. As many as 15 hairs may be associated with one pore. Usually in compound follicles a single long primary hair (also known as a guard hair or cover hair) is surrounded by shorter secondary hairs called satellite hairs. In dogs, usually three compound follicles are grouped together to emerge from the same epidermal fold. Hair is formed in three concentric layers. The innermost layer (and central core) is called the medulla. It is composed of two to three layers of loosely arranged cells that are separated by spaces filled with liquid or air. The cells themselves contain flexible, soft keratin similar to that found in the stratum corneum of the epidermis. Surrounding the medulla is the cortex. Unlike the flexible medulla, the cortex is stiff and rigid because it is composed of hard keratin and is the thickest of the three layers. A single layer of cells arising from the edge of the papilla form the hair surface, the cuticle, which is also composed of hard keratin. The cells of the cuticle are layered like shingles on a roof, which prevents the hairs from sticking together and forming mats. In some animals such as sheep, however, the edges of the cells in the cuticle are raised, enabling them to grab onto the cuticle cells from other hair strands.

Is a solution with a pH of 8.5 acidic or basic?

3. Basic

The digestion of food does which type of chemical reaction?

3. Decomposition reaction

What process joins multiple simple sugars?

3. Dehydration synthesis

Can you list all 5 layers of the epidermis? What is happening in each layer?

3. From the innermost layer outward: 1. The stratum germinativum, also known as the stratum basale (basal layer). For the most part, this layer consists of a single row of keratinocytes, which are firmly attached to the epithelial basement membrane and actively engaged in cell division. New daughter cells move from the stratum basale to sequentially more superficial layers as they mature. In this way, they replace epithelial cells that have exfoliated at the skin's surface. Merkel cells and melanocytes are found in this layer. 2. The stratum spinosum (the prickle-cell layer). The stratum spinosum (spiny layer) is so named because when the cells of this epidermal layer are fixed for histologic exam, they contract into speculated masses that resemble sea urchins. It contains several layers of cells that are held together by desmosomes. 3. The stratum granulosum (granular layer) is the middle layer of skin. Composed of two to four layers of flattened, diamond-shaped keratinocytes, the stratum granulosum is the highest level of the epidermis where living cells can be found. The cytoplasm of these cells begins to fill with keratohyalin and lamellated granules, which in turn leads to the dramatic degeneration of the nucleus and other organelles. Without these vital parts, the cell quickly dies. The lamellar granules contain waterproofing glycolipids and are transported to the periphery of the cell, where their contents are discharged into the extracellular space. These glycolipids play an important role in waterproofing the skin and slowing water loss across the epidermis. 4. The stratum lucidum (clear layer) is found only in very thick skin. Most skin, therefore, lacks this layer. Microscopically, the stratum lucidum appears as a translucent layer composed of a few rows of flattened dead cells. In this and the outermost epidermal layer, the sticky contents of the keratogranules combine with intracellular tonofilaments to form keratin fibrils. 5. The stratum corneum (horny layer) is the outermost layer and dominates the epidermis. It constitutes up to three quarters of the total epidermal thickness and is composed of 20 to 30 rows of keratinocytes. On sagittal section, the cells are paper thin and almost two dimensional, yet when viewed from above, they appear hexagonal. These are really only the remnants of keratinocytes, because the actual cells died in the stratum granulosum. They are sometimes called horny or cornified cells, but we commonly call them dandruff and recognize them as the flakes that occasionally drop on our shoulders.

In what circumstance does a hydrogen bond commonly occur?

3. Hydrogen bonds are formed mostly between molecules (for example, between water molecules) and act to stabilize the solution. Hydrogen bonding is the key to water's unique properties as a universal solvent and a medium for the life processes. Hydrogen bonds can also form between parts of the same molecule. This works to stabilize and hold the shape of large, complex molecules such as proteins and DNA.

What is the name of the bond holding two amino acids together?

3. Peptide bond

Which lipids are polar: neutral fats or phospholipids?

3. Phospholipids

What are the four types of inorganic & organic molecule that are important for life?

3. Water, salts, and acids and bases 4. Carbohydrates, lipids, proteins, and nucleic acids

Describe the parts of the hair follicle and explain how hair grows.

A hair follicle is an invagination of the epidermis that extends from the skin surface to the dermis or, occasionly, to the hypodermis The deepest part expands to form a hair bulb At the base of the bulb is a mound of dermal cells called the Papilla, which is covered with rapidly dividing cells called the Matrix The cells are nourished by blood flow from vessels in the underlying papilla A web of sensory nerve endings called the root hair plexus envelops the root, making it an important touch receptor when the hair is bent. The wall of the hair follicle is composed of 3 layers: an internal epithelial root sheath, and outer epithelial root sheath, and a dermal or connective tissue root sheath Nourishment of the epithelial cells stimulates much cell division and growth. As the cells divide, all their cells are pushed upward into the tunnel away from the papilla. These cells become keratinized, and as they lose contact with the nutrition provided by the papilla, they die and become part of the developing hair. In this way hair is constructed from dead epithelial cells Anagen phase: hair growth Telogen phase: hair stops growing, hair follicle shortens, and hair is held in a resting phase (for weeks to years) Catagen phase: period of transition between anagen and telogen phases

How do changes in the osmolality of body fluids affect an animal's desire to drink and its ability to concentrate or dilute urine?

A hormonal feedback loop helps maintain the osmolality of body fluids within a very narrow range. An increase in the osmolality of blood, for example, stimulates the desire to drink and the release of antidiuretic hormone (ADH) in the pituitary. ADH, in turn, stimulates the kidney to resorb water from protourine resulting in the concentration of urine. The opposite happens if the osmolality of blood becomes too low. The release of ADH in the brain is repressed and urine becomes concentrated via active removal of water from protourine in the kidney.

What are the differences among a skeletal muscle fiber, a skeletal muscle myofibril, and a skeletal muscle protein filament

A muscle fiber is one muscle cell. The muscle fiber is made up of many muscle myofibrils. Within the myofibrils are muscle the protein filaments myosin and actin.

What is the result of a normal PLR?

A normal response to shining a light into the eye of an animal (pupillary light reflex [PLR]) is for the iris in both eyes to constrict, thus making both pupils smaller.

What defines a passive membrane process?

A passive membrane process is one that does not require energy (ATP).

How do histones play a role in gene regulation?

A single strand of DNA winds around eight histone molecules, forming a granule called a nucleosome. The nucleosomes are held together by short strands of DNA called linker DNA. Not only do the histone proteins help keep the DNA strand organized and untangled, but they also expose small sections of the DNA (genes) to the outside nucleoplasm. By changing shape, the histones can expose different sections of DNA, called genes, at different times. A gene is the length of DNA needed to make one peptide (a short chain of amino acids). The exposed genes determine what proteins will be made by the cell. In this way, histones play an important role in regulating gene expression (gene regulation). DNA contains the instructions required for synthesis of thousands of different proteins, but not all of them are made. Only a small percentage of the possible thousands of proteins are actually manufactured. Histones help determine which segments of DNA will be expressed and therefore which proteins will be made.

What is the sensory receptor in the stretch reflex? What results from the stretch reflex arc stimulation? Is this an ipsilateral or contralateral reflex?

A specialized structure within the muscle called the muscle spindle. Muscle contraction results. Ipsilateral.

Define homeostasis.

A state of equilibrium maintained in the body by feedback and regulatory processes in response to internal and external changes; the maintenance of balance in the body. The concept of homeostasis includes the many mechanisms that monitor critical levels and functions in the body and stimulate corrective actions when things stray from normal. By keeping important activities within relatively narrow ranges, the process of homeostasis helps maintain normal body structure, function, and therefore health.

What happens in a withdrawal reflex? Is this reflex more or less complex than the stretch reflex?

A strong stimulus to a receptor causes the sensory somatic neuron to send impulses to the spinal cord. This reflex involves synapsing with several interneurons. Some of these interneurons will synapse with motor neurons that will cause contraction of a specific set of muscles responsible for pulling the limb away from the painful stimulus. Other interneurons will inhibit those opposing muscle groups so that the withdrawal of the limb is rapid and complete. This reflex is more complex than a stretch reflex.

What is an element?

A substance that contains only ONE type of atom. 1. An element is matter that cannot be divided by ordinary chemical processes into another substance.

11-3 Through what mechanisms does the hypothalamus control the production or release of hormones from the pituitary gland? How do its affects on the anterior and posterior portions of the pituitary differ?

A system of tiny blood vessels called a portal system links the hypothalamus with the anterior portion of the pituitary gland. Modified neurons in the hypothalamus secrete hormones into these portal blood vessels. The hormones travel the short distance down to the anterior pituitary and regulate much of its function. These hypothalamic hormones, called releasing and inhibiting factors, are each specific for a particular anterior pituitary hormone. As their names imply, a releasing factor causes the anterior pituitary to produce and release a particular hormone, and an inhibiting factor has the opposite effect of inhibiting the production and release of a hormone. Because some anterior pituitary hormones influence all of the body's cells, the hypothalamus indirectly affects the whole body by regulating anterior pituitary gland functions. The effect of the hypothalamus on the posterior part of the pituitary gland is more direct. Modified neurons in the hypothalamus produce two hormones, antidiuretic hormone and oxytocin, that are transported down nerve fibers to the posterior pituitary gland, where they are stored. They are then released into the bloodstream by nerve impulses from the hypothalamus.

8-2 What is the difference between a tendon and an aponeurosis

A tendon is a band of fibrous connective tissue that attaches muscle to bone. An aponeuroses is a broad sheet of fibrous connective tissue.

List the locations and actions of muscles of the abdomen, thoracic limb, and pelvic limb

ABDOMINAL, FROM OUTSIDE IN: Support the abdominal organs, help flex arch the back and participate in various functions that involve straining, such as defecation, urination, parturition, the processes of vomiting and regurgitation, and respiration EXTERNAL ABDOMINAL OBLIQUE - Run in a caudoventral (backward and downward) direction INTERNAL ABDOMINAL OBLIQUE - Run in opposite direction, cranioventral or forward and downward RECTUS ABDOMINIS - Forms the floor (ventral portion) of the muscular abdominal wall. It consists of 2 strap like muscles on either side of the linea Alba that run from the ribs and sternum back to the brim of the pubis TRANSVERSUS ABDOMINIS - The deepest of the abdominal muscles. Its fibers run directly downward in a venture direction to insert on the linea Alba. The left and right parts of each muscle come together on the ventral midline at the Linea Alba THORACIC LIMB: Function mainly in locomotion, allowing the animal to walk, run, and generally move around its environment. Superficial muscles of the shoulder region: LATISSIMUS DORSI - A broad, triangular muscle that extends from the spinal column down to its insertion on the humerous. It flexes the shoulder which helps propel the body forward PECTORAL - 2 of them, one superficial and 1 deep, located on each side of the sternum. They both extend from the sternum to the humerous and act as adductor muscles (inward movers) of the front leg. They help keep the front legs under the animal and prevent them from splaying out to the sides DELTOID - Triangular, extends from the lateral portion of the scapula down to the humerous. It is an abductor muscle (outward mover) and flexes the shoulder joint Upper arm (brachium): BICEPS BRACHII - Has teo proximal head attachments and extends from the distal end of the scapula to the proximal end of the radius. When it contracts, it flexes the elbow joint TRICEPS BRACHII - Has 3 proximal head attachments and extends from the distal scapula and proximal humerus down to the olecranon process of the ulna (the point of the elbow). When it contracts it extends the elbow joint Distal to the elbow joint: EXTENSOR CARPI RADIALIS - Extends the carpus and is located over the radius DEEP DIGITAL FLEXOR - Flexes the digit and is located beneath some of the other digital flexor muscles PELVIC LIMB: Mainly involved in locomotion. Extensor muscles of the hip joint. Help propel the body forward by extending the hip joint pulling the leg backwards GLUTEAL - Extend from the bones of the pelvis down to the trochanters of the femur HAMSTRING - 3 muscles located on the caudal part of the thigh region. All 3 help extend the hip joint and are the main flexors of the stifle joint: BICEPS FEMORIS - SEMIMEMBRANOSUS - SEMITENDINOSUS - QUADRICEPS FEMORIS - Main extensor muscle of the stifle joint. It is located in the cranial part of the thigh region. When an animal has taken a stride with its hind leg, the quadriceps femoris muscle helps bring the leg forward to prepare for the next stride. Composed of four heads. GASTROCNEMIUS - The equivalent of our main calf muscle. It extends from the caudal portion of the distal end of the femur and inserts on the calcaneal tuberosity of the fibular tarsal bone (the point of the hock). ACHILLES TENDON - the distal Gastrocnemius Tendon in humans attaches to our heel and is called the Achilles tendon. It is a powerful extensor muscle of the hock. It also helped propel the body forward as an animal takes a stride

Describe the effects of androgens, estrogens, and progestins

ANDROGENS - Male sex hormones, mainly testosterone - Causes development of male secondary sex characteristics such as muscular male body shape and libido, development of male accessory sex glands - activates spermatogenesis, and stimulates growth of the penis. - Steroid hormone, anabolic effect in that it stimulates the buildup of proteins in muscle and bone ESTROGENS - Female sex hormones - physical and behavioral changes that prepare a female for breeding and pregnancy, - signal male it's time to breed - produced by ovarian follicle PROGESTINS - Progesterone - pregnancy promoting steroid hormone - prepares uterus to receive the fertilized ovum - is necessary for pregnancy to be maintain once ovum is implanted - produced by empty follicle called the Corpus Luteum

List the major endocrine glands and the hormones they produce

ANTERIOR PITUITARY Growth hormone Prolactin Thyroid stimulating hormone Adrenocorticotropic hormone Follicle stimulating hormone Luteinizing hormone Melanocyte-stimulating hormone POSTERIOR PITUITARY Antidiuretic hormone Oxytocin THYROID Thyroid hormone Calcitonin PARATHYROID Parathyroid hormone ADRENAL CORTEX Glucocorticoid hormones Mineralocorticoid hormones ADRENAL MEDULLA Epinephrine and Norepinephrine PANCREAS (ISLETS) Insulin Glucagon TESTIS Androgens OVARY estrogens Progestins

How is acetylcholine different from acetylcholinesterase?

Acetylcholine is a neurotransmitter broken down quickly by an enzyme called acetylcholinesterase found on the postsynaptic membrane. The broken down components of acetylcholine are reabsorbed by the synaptic knob, reassembled into new acetylcholine molecules, and repackaged into vesicles for release with the next wave of depolarization.

Differentiate between areolar, adipose, and reticular connective tissues

All are loose connective tissue Areolar - Most common type of connective tissue, found everywhere in the body. A beautiful tangle of randomly placed fibers and cells suspended in a thick, translucent ground substance. Acts as packing material to support and cushion organs and other delicate structures of the body. It surrounds every organ, forms the subcutaneous layer that connects skin to muscle, envelops blood vessels, nerves, and lymph nodes, and is present in all mucous membranes as the lamina propia and submucosa. Supportive of body structures but flexible and soft to and able organs to move. Moderately elastic but tears easily compared to other types. Adipose - Fat. Areolar Tissue in which adipose sites or fat cells predominate. Found beneath the skin, in spaces between muscles, behind the eyeballs, on the surface of the heart, around the joints, in bone marrow, and in the omentum of the abdomen. Adipose tissue is highly vascularized so that the liquid droplets within are accessible to the enzymes responsible for triglyceride breakdown and to a bloodstream that readily transports the glycerol and free fatty acid products to other parts of the body. Adipose tissue represents an important energy store for animals, acts as a thermal insulator under the Skin, prevents heat loss from the body, and access a mechanical shock absorber around organs such as the kidneys. white adipose tissue - Found throughout the body, particularly in the deep layers of the skin brown adipose tissue - Found in newborn animals and in animals that hibernate during the Winter. Highly specialized, plays an important part in temperature regulation because it is the site of heat production. Lipids are stored in multiple small difficulties instead of single large droplets and the energy released from the oxidation of the liquids and released from electron transport is dissipated as heat rather than ATP. Has a high number of mitochondria. Reticular - Composed of a complex 3-dimensional network of thinner reticular fibers. Resembles areolar connective tissue and that it contains loosely arranged fibers and many fiber blasts, but unlike areolar connective tissue it contains only one type of fiber, "reticular fibers". Together the cellular and matrix components form a network called STROMA which constitutes the framework of several organs such as the liver, spleen, lymph nodes, and bone marrow. Although reticular fibers are found throughout the body, reticular connective tissue is found in a limited number of sites

Can a cell with no nucleus live as long as a cell with one, why or why not?

All cells have different life spans: some are very short lived, while other cells live a long time. However, a cell that lacks a nucleus does not have the instructions (DNA) to make protein and therefore it cannot repair itself and will die sooner than if it had the ability to repair and maintain itself.

What is an electrolyte?

An electrolyte is a charged particle (an anion or a cation) capable of conducting an electric current in solution.

Define the terms anatomy and physiology.

Anatomy - is the study of the form and structure of an animal body and its parts (healthy). Through anatomy, we can describe where things are located in or on the animal body and what they look like. Physiology - is the study of the functions of the animal body and its parts. Through physiology, we can describe how parts of the body work and what their functions are.

Describe how sodium and potassium enter and exit the cell.

Because of the concentration gradients of sodium (Na+) and potassium (K+), potassium tends to diffuse out of the cell and sodium diffuses in. To maintain appropriate levels of intracellular potassium and extracellular sodium, the cell must pump potassium into the cell and pump out sodium. Because diffusion is ongoing, the active transport system must work continuously. The rate of transport depends on the concentration of sodium ions in the cell. ATP is provided by cellular respiration and, with the assistance of the enzyme ATPase, is broken down for use as energy on the inner surface of the cell membrane. The pump can cycle several times using just one molecule of ATP, so that for every molecule of ATP, two potassium ions are moved intracellularly and three sodium ions are moved extracellularly.

How do the clinical signs of hypothyroidism and hyperthyroidism relate to the normal functions of thyroid hormone?

Because thyroid hormone influences the functioning of all cells, organs, and systems, hypothyroidism affects the whole body. Clinical signs relate primarily to a slowing of the body's metabolism and include alopecia (hair loss, usually bilaterally symmetrical), dry skin, lethargy, reluctance to exercise, and weight gain without any increase in appetite. An affected animal often seeks out sources of heat because deficient thyroid hormone levels cause the animal to have difficulty maintaining its body temperature. Most cases of hypothyroidism occur in middle-age animals, but if it occurs in a young animal, dwarfism (impaired growth) and impaired mental development occur along with the other common signs. Hyperthyroidism is most commonly seen in cats, although it is seen occasionally in dogs. Excessive amounts of thyroid hormone speed up cellular metabolism all over the body. This results in signs such as nervousness, excitability, weight loss, increased appetite, tachycardia (abnormally fast heart rate), vomiting, diarrhea, polyuria (excessive urine production), and polydipsia (excessive thirst).

Even though blood and bone appear to be grossly different, they both represent types of connective tissue. Why?

Blood and bone both contain cells, a matrix, and extracellular fibers.

What is another name for hydrostatic pressure in the body?

Blood pressure

According to the principle of bilateral symmetry, single structures in the body are located on or near which anatomical plane of reference?

Median plane

What is bone marrow, and what is the difference between the red kind and the yellow kind?

Bone marrow fills the spaces within bones. This includes the small spaces between the spicules of cancellous bone and the large spaces within the diaphyses of long bones. Red bone marrow is the part of the bone that forms blood cells. It makes up the majority of the bone marrow of young animals but only a small portion of the marrow of older animals. Yellow bone marrow is primarily made up of adipose connective tissue (fat). It is the most common type of marrow in adult animals. Yellow bone marrow does not produce blood cells, but it can revert to red bone marrow if the body needs to churn out larger than normal numbers of blood cells.

10-2 How are the senses of taste and smell similar? How are they different?

Both are chemical senses. Whereas many nonhuman animals have less perceptive eyesight but a highly acute sense of smell, humans have a less perceptive sense of smell and a highly acute sense of taste.

10-4 How is the functioning of the vestibule and the semicircular canal similar? How is it different?

Both have endolymph- and perilymph-filled structures. The crista of the semicircular canals is similar to the macula of the vestibule. Both have supporting cells and hair cells with their processes (modified dendrites) sticking up into a gelatinous structure. However, there are no otoliths in the semicircular canals to weigh down the cupula. Instead, it functions as a float that moves with the endolymph in the membranous canal. Whereas the vestibular system senses rotary motion of the head with the semicircular canals, the vestibule senses linear motion and position of the head.

Compare and contrast the molecular structure of DNA and RNA.

Both made up of nucleotide says I trogilus base, 5 carbon sugar, phosphate group pretty alternate sugar and phosphate in a backbone, the trudging his base sticks out. DNA = double strand, deoxyribose sugar; adenine, cytosine, guanine, thymine RNA = single strand, ribose sugar; adenine, cytosine, guanine, uracil

In what ways are the functions and characteristics of the enocrine system similar to those of the nervous system? In what ways are they different?

Both systems regulate body functions to maintain homeostasis. The endocrine system's reaction to stimuli is slow, whereas the reaction of the nervous system to stimuli is fast. The endocrine system's duration of effects is long, whereas the duration of effects of the nervous system is short. The target tissues for the endocrine system are virtually all body cells and tissues, whereas the target tissues for the nervous system are muscle and glandular tissues. The chemical messengers of the endocrine system are hormones, whereas the chemical messengers of the nervous system are neurotransmitters. The messenger-producing cells of the endocrine gland are cells or modified neurons, whereas the messenger-producing cells of the nervous system are neurons. The distance from chemical message production to the target for the endocrine system is long (via the bloodstream), whereas this distance for the nervous system is short (across the synaptic space).

Which part of the brain controls many autonomic functions related to cardiovascular, respiratory, and gastrointestinal functions?

Brain stem

What are caveolae and what role do they play in the cell membrane?

Caveolae are minute invaginations of the cell membrane, like tiny dimples. Caveolae often pinch off entirely from the cell membrane, forming vesicles. These vesicles can form singly or in clusters (like tiny rosettes). Caveolae are formed only from rafts in the cell membrane that contain the protein caveolin.

Why might it be of clinical importance to know the origin and insertion of a muscle?

By knowing the origin and insertion of a muscle, you can predict the action of the muscle without actually seeing the muscle contract.

If individual muscle fiber contractions obey the all-or-nothing principal, how does an animal control the size and strength of its muscular movements?

By the number of fibers in a muscle that contract

What are CAMs & what do they do?

CAM refers to cell adhesion molecules, which are sticky glycoproteins (part of the glycocalyx) that cover the surfaces of almost all cells in mammals and allow them to bond to extracellular molecules and to each other. These molecules are also important in helping cells move past one another and in signaling circulating cells, such as white blood cells, to areas of inflammation or infection.

List the components of carbohydrates, lipids, proteins, and nucleic acids.

CARBOHYDRATES These are sugars and starches. Used for energy, storage of energy, and cellular structures. They are all composed of only three atoms: carbon, hydrogen, and oxygen, with hydrogen and oxygen in a 2:1 ratio Three types of these which are: 1. Monosaccharides 2. Disaccharides 3. Polysaccharides LIPIDS Made of carbon, hydrogen, and oxygen, though their oxygen content is much lower. They also sometimes contain phosphorus. - Used in the body for energy in are stored in fat for future energy needs. Serve as chemical messengers in the form of some hormones - There are four classes that are important for life: - neutral fats ‐ plant (unsaturated) and animal (saturated) fats, used for energy - phospholipids - hydrophobic tail and hydrophilic head: lipid bilayer - steroids - hydrophobic, nonvolatile, very little O². cholesterol, used used for creation of steroid hormones - eicosanoids - lipids formed from a 20‐carbon fatty acid and a ring structure. Important substances for the mediation of complex chemical processes PROTEINS Most abundant organic molecules in the body. They have the widest variety of functions. Organic molecules composed of carbon, oxygen, hydrogen, and nitrogen - some also contain sulfur, iron common or phosphorus All are composed of the same twenty amino acids. Sequence of amino acids determines the function of the protein. NUCLEIC ACIDS Composed of carbon come oxygen, hydrogen carbon nitrogen, and phosphorus. DNA and RNA. The genetic information within cells that determines what we look like. Composed of nucleotides linked by covalent bonds

Describe the structures and functions of the cerebrum, cerebellum, diencephalon, and brainstem

CEREBRUM: - Largest part of the brain in domestic animals and constitutes the area of the brain responsible for those functions most commonly associated with higher order behaviors, such as learning, reasoning, and intelligence. - Receives and interprets sensory information, initiate conscious (voluntary) nerve impulses to skeletal muscles, and integrates neuron activity that is normally associated with communication, expression of emotional responses, learning, memory and recall, and other behaviors associated with conscious activity - Is neurons of certain lobes begin to fire spontaneously as a result of drugs, cellular damage, or neurotransmitter imbalance, the animal can exhibit spontaneous movements, seizure activity, of normal behaviors, or hallucinations, depending on which lobes are affected. - If parts become damaged and nonfunctional From lack of oxygen, poisonous substances camo or blood clots (strokes), the animal may lose the perception of specific sensations, may experience loss of voluntary movement, or may be unable to retain or recall information (unable to learn) Cerebral cortex - The outer most superficial layer of the brain Corpus callous - A set of fibers that connects the 2 halves of the cerebral cortex Gyri (gyrus = single) - folds Fissures - deep grooves Sulci (sulcus = single) - shallow grooves Longitudinal fissure - Most prominent groove, which divides the cerebrum into right and left cerebral hemispheres Cerebral hemispheres - Right and left sides of the brain Lobes - Each hemisphere is divided by sulci into lobes. Different lobes specialize in certain functions. CEREBELLUM: - Located caudal to the cerebrum, is the second largest component of the brain. Has a wrinkled appearing surface, and a Gray matter cortex with white matter beneath it. - Allows the body to have coordinated movement, balance, posture, and complex reflexes. - Compares the movement the body intends to make with the actual position of muscles and joints to determine whether the intentions of the cerebral cortex are actually being carried out. If not being carried out accurately, the cerebellum will stimulate or inhibit muscles to fine tune the movements (makes it smooth and accurate) - Damage can result in Hypermetria, a condition in which voluntary movements become jerky and exaggerated DIENCEPHALON: - Not as physically defined as the cerebrum and cerebellum. - Does not have clearly visible layers of Gray matter and white matter. - Serves as in nervous system passageway between the primitive brain stem and the cerebrum. Thalamus - acts as a relay station for regulating sensory inputs to the cerebrum Hypothalamus - An interface between the nervous system and the endocrine system Pituitary - The endocrine master gland that regulates production and release of hormones throughout the body BRAINSTEM: - Connection between the rest of the brain and the spinal cord. Most primitive part of the brain. Does not have clearly visible layers of Gray matter or white matter. - Main role is to maintain basic support functions of the body so it operates at the subconscious level. - Heavily involved in autonomic control functions related to the heart, respiration (including coughing, sneezing, and hiccuping), blood vessel diameter, swallowing, and vomiting. Many cranial nerves originate from this area of the brain. Damage can be fatal. Medulla oblongata Pons Midbrain

Describe the structure of the conjunctiva and eyelids

CONJUNCTIVA - Thin, transparent membrane that covers the front portion of the eyeball and lines the interior surfaces in the eyelid - BULBAR CONJUNCTIVA - front of eye - PALPEBRAL CONJUNCTIVA - eyelids - CONJUNCTIVAL SAC - space between Bulbar and Palpebral EYELIDS - Consist of upper and lower fold of skin, lined by the conjunctiva - CANTHI (lateral and medial) - lateral and medial corners where the eyelids come together - TARSAL GLANDS (meibomian glands) - Tiny openings along margin of each eyelid - produce waxy substance that prevents tears overflowing - NICTITATING MEMBRANE (3rd eyelid) - Located medially between eyelids and eyeball - T shaped plate of cartilage covered by conjunctiva; no muscles, movements are passive, ocular surface has lymph nodes and tear glands

List and describe the types of chemical bonds that may form between elements.

COVALENT - shared electrons, strong bond, electrons spend time in each electron shell - Polar molecule - Electrons spend more time with one atom, has a slight charge (H20) ‐ Organic molecules IONIC - electrons are transferred, tend to occur between nearly empty or nearly full outer shells - Inorganic molecules (electrostatic charge keeps them together) HYDROGEN - weak, formed by electrostatic attraction between 2 hydrogen atoms - gives water its unique properties, help stabilize complex molecular structure in large molecules

Name the internal and external bones of the face and cranium

CRANIUM Frontal 2 Interparietal 2 Occipital 1 Parietal 2 Temporal 2 INTERNAL CRANIUM Ethmoid 1 Sphenoid 1 EAR none external INTERNAL EAR Incus 2 Malleus 2 Stapes 2 FACE Incisive 2 Lacrimal 2 Mandible 2 maxillary 2 Nasal 2 Zygomatic 2 INTERNAL FACE Palatine 2 Pterygoid 2 Turbinates 4 Vomer 1

Explain the functions of the cerebrospinal fluid

CSP = Clear, slippery liquid that circulates between layers of the meninges and through cavities inside the brain and spinal cord - Cushions the brain - Chemical composition may be involved in regulation of certain autonomic functions such as respiration and vomiting

8-4 What ion, released from the sarcoplasmic reticulum by a nerve impulse, starts the contraction process in a muscle fiber?

Calcium

Differentiate between cancellous and compact bone

Cancellous (spongy) - Made up of tiny spicules of bones with lots of space between them, light but strong Compact - Very dense and strong - made up of laminated cylinders of bone called Haversian Systems - outside of all bones and shafts of long bones

What are the main differences between the structures of cancellous bone and compact bone? Why does the body need these 2 different types of bone?

Cancellous bone consists of tiny spicules of bone randomly arranged with lots of spaces between them. In life, the spaces between spicules are occupied by bone marrow. To the naked eye, the many spicules and spaces give cancellous bone its spongy appearance. It is light but amazingly strong and helps reduce the weight of the bones of the skeleton without significantly reducing their strength. The organization of the spicules of cancellous bone may appear random, but spicules are actually arranged to stand up to the forces the bone is subjected to. Alternatively, compact bone is very heavy and dense. It is composed of tiny, tightly compacted cylinders of bone called haversian systems. Each haversian system runs lengthwise along the bone and consists of a laminated (multilayered) cylinder composed of concentric layers of ossified bone matrix arranged around a central canal. The haversian canal contains blood and lymph vessels and nerves that supply the osteocytes. The osteocytes are located at the junctions between the layers of bone that make up each haversian system. Two different types of bone are important because cancellous bone keeps an animal's body weight lower, being lighter than compact bone. Both types of bone are needed to stand up to the stresses encountered by an animal's skeleton.

8-5 Describe a cardiac muscle cell in terms of size, shape, number of nuclei, and appearance under the microscope

Cardiac muscle is striated but smaller than skeletal muscle cells. These muscles have only one nucleus per cell. The cardiac muscle cells are longer than they are wide and have multiple branches. They are attached to each other by intercalated discs.

What are catecholamines?

Catecholamines are the neurotransmitters norepinephrine, epinephrine, and dopamine.

Give a specific example of both cations and anions.

Cations are positively charged and include potassium (K+), magnesium (Mg2+), calcium (Ca2+), and sodium (Na+). Anions are negatively charged and include sulfate (SO42-), hydrogen phosphate (HPO4 2-), chloride (Cl-), and bicarbonate (HCO3-). [Refer to textbook Figure 4-3 for clarification on how to write out the chemical formula for each anion and cation.]

Why must the term rostral be used instead of cranial to describe structures on a hedgehog's head, but the term caudal works just fine?

Caudal always means toward the tail end of the body. The cranium is part of the head, therefore the term cranial loses its meaning. Rostral specifically means toward the tip or nose.

Which are found more commonly in mammalian cells: cilia or flagella?s

Cilia

How are cilia and flagella different?

Cilia occur in large numbers on the exposed surface of some cells. They are shorter than flagella and measure only about 10 mm long. They move synchronously, one after the other, creating waves of motion that propel fluid, mucus, and debris across the cell surface. Cilia are best known for their important functions (1) in the upper respiratory tract, where they propel bacteria and mucus away from the lungs, and (2) in the oviduct, where their beating motion pulls the ovulated egg away from the ovary and into the opening of the oviduct. Flagella generally occur singly and are significantly longer than cilia. They are typically attached to individual cells and propel the cell forward by undulating. Flagella move cells through fluid, whereas cilia move fluid across cell surfaces. The tail of a sperm cell is an example of a flagellum.

Compare and contrast collagenous, reticular, and elastic fibers

Collagenous fibers are strong, thick strands composed of the structural protein collagen. Collagen fibers are organized into discrete bundles of long, parallel fibrils, which in turn are composed of bundled microfibrils. Because they possess tremendous tensile strength enabling them to resist pulling forces, collagenous fibers are found in tendons and ligaments that are continually being pulled and stretched. When not under pressure, collagenous fibers look wavy. The fiber itself is white, and the tissue it forms when the fibers are packed closely together is also white. Therefore, it is not surprising that collagenous fibers are sometimes known as the white fibers. Reticular fibers, like collagenous fibers, are composed of collagen, but they are not thick. Instead they are thin, delicate, and branched into complicated networks. Reticular fibers form a kind of "mist net" (rete is Latin for "net") that provides support for highly cellular organs such as endocrine glands, lymph nodes, spleen, bone marrow, and liver. Elastic fibers are composed primarily of the protein elastin. Like reticular fibers, elastic fibers are branched and form complex networks, but they lack the tensile strength of collagenous fibers. Elastic fibers are composed of bundles of microfibrils, and because they are coiled, they can stretch and contract like a rubber band. Therefore, elastic fibers tend to occur in tissues that are commonly subjected to stretching (vocal cords, lungs, skin, and walls of blood vessels). Because of their color, elastic fibers are sometimes referred to as the yellow fibers.

List and describe the components of cytoplasm.

Cytosol: The cytosol is the semi-fluid component or liquid medium of a cell's cytoplasm. It is located outside of the nucleus and within the cell membrane. Organelles: Organelles are tiny cellular structures that perform specific functions within a cell. Examples of organelles include mitochondria, ribosomes, nucleus, lysosomes, chloroplasts, endoplasmic reticulum, and Golgi apparatus. Also located within the cytoplasm is the cytoskeleton, a network of fibers that help the cell maintain its shape and provide support for organelles. Cytoplasmic Inclusions: Cytoplasmic inclusions are particles that are temporarily suspended in the cytoplasm. Inclusions consist of macromolecules and granules. Three types of inclusions found in the cytoplasm are secretory inclusions, nutritive inclusions, and pigment granules. Examples of secretory inclusions are proteins, enzymes, and acids. Glycogen (glucose storage molecule) and lipids are examples of nutritive inclusions. Melanin found in skin cells is an example of a pigment granule inclusion.

Why is it important for chromatin to coil and form discrete chromosomes before the cell division?

DNA is a very long, cumbersome, and delicate molecule. The formation of duplicate, supercoiled chromosomes is essential for life and enables the cell to divide its genetic material equitably for a new generation, without tangling or breaking the long, delicate chains of genetic code.

When in the cell cycle does DNA replication occur?

DNA replicates during the synthetic (S) phase of interphase.

Name the parts of a typical neuron

Dendrite, axon, and cell body

How are the dendrites and axons different in structure and function?

Dendrites receive stimuli, or impulses, from other neurons and conduct this stimulation to the cell body. Dendrites also may be modified into sensory receptors that receive, or sense, stimuli, such as heat, cold, touch, pressure, stretch, or other physical changes from inside or outside the body. Dendrites tend to be short, numerous, multibranched projections extending from the cell body. The axon conducts nerve impulses away from the cell body toward another neuron or an effector cell (a cell that does something when stimulated, such as a muscle or gland cell). In contrast to the short, numerous, branched dendrites, the axon is a single structure that can be very long. For example, a single axon in the horse may extend several feet from the spinal cord all the way to the lower leg. Axons are often covered by a fatty substance called myelin.

What part of the brain serves as a relay station for impulses going to and from the cerebrum?

Diencephalon

Draw a picture of each of the following types of epithelioma and give an example of where each of them can be found in the body. Simple squamous Simple cuboidal Simple columnar Stratified squamous Pseudo stratified columnar Transitional

Drawings should represent the following descriptions: • Simple squamous epithelium can be found in the inner lining of the lung (where oxygen is absorbed and carbon dioxide released) and in the filtration membranes of kidneys (where water and other small molecules are excreted as urine). • Simple cuboidal epithelium can be found on the surface of ovaries; in the secretory portions of glands, such as the thyroid; and in the lining of the ducts of the liver, pancreas, kidney, and salivary gland. • Simple columnar epithelium is found lining the length of the gastrointestinal tract from the stomach to the rectum. • Stratified squamous epithelium is found lining the mouth, esophagus, vagina, and rectum. • Pseudostratified columnar epithelium is found in the respiratory tract and in portions of the male reproductive tract. • Transitional epithelium is found in portions of the urinary tract where great changes in volume occur (urinary bladder, ureters, urethra, and calyxes of the kidney).

Describe the structure and function of the components of the ear

EXTERNAL EAR Access a funnel to collect sound wave vibrations and direct them to the ear drum - Pinna - The part of the ear we can see from the outside. A funnel-like structure composed mainly of elastic cartilage and skin that collects sound wave vibrations and directs them into the external auditory canal - External auditory canal - a soft, membrane lined tube the begins at the base of the pinna and carries sound waves to the tympanic membrane. somewhat L-shaped. - Tympanic membrane (eardrum) - Paper-thin connective tissue membrane that is tightly stretched across the opening between the external auditorium canal and the middle ear cavity. When sound wave vibrations strike it, it vibrates at the same frequently through a process called sympathetic vibration MIDDLE EAR Amplifies and transmits the vibrations from the eardrum to the inner ear - Ossicles - 3 small bones that link the tympanic membrane with the cochlea of the inner ear - Eustachian tube - Connects the middle ear with the pharynx (throat), equilizes pressure on both sides of the tympanic membrane - Cochlea - Where the receptors for hearing are located. Snail shell shaped spiral cavity in the temporal bone - Malleus - hammer, outermost, attached to tympanic membrane - Incus - anvil, middle bone - Stapes - stirrup, medial-most, attached to the membrane that covers the oval window of the cochlea (ossicles are connected by synovial joints) INNER EAR Contains the actual sensory receptors that convert the mechanical vibrations to nerve impulses, along with receptors for the equilibrium sense - Organ of Corti - The receptor organ of hearing, located in the cochlea. It consists of hair cells with a gelatinous structure resting on the hairs surrounded by fluid. Vibrations of the fluid cause distortion of the hairs, which generates nerve impulses that are interpreted by the brain as sound - Cochlear Duct - Long tube that runs the length of the cochlea, where the organ of Corti sits - Endolymph - Fluid that fills the Cochlear duct - Perilymph - Fluid that sits in a U-shaped tube that lies on either side of the cochlear duct - Oval window - Located at the base of the cochlea, the stapes is attached to it - Round window - Located at the base of the cochlea, nothing sits against it - Tectorial membrane - Gelatin like membrane that lies on top of the hairs in the organ of Corti. Sound wave vibration causes It to move which bends the hair cells and generates nerve impulses

What is the difference between endocrine and exocrine glands? Can you give examples of each?

Endocrine glands do not have ducts or tubules, and their secretions are distributed throughout the body. They produce and secrete regulatory chemicals known as hormones into the bloodstream or the lymphatic system, where they are carried to many regions of the body. The pituitary gland in the brain and the adrenal gland near the kidney are examples of endocrine glands. Exocrine glands possess ducts. They are more common than endocrine glands and act by discharging secretions through their ducts directly into local areas, where they may cover cell surfaces or empty into body cavities. The secretions of exocrine glands act locally and do not normally enter the circulation. Examples include hepatoid, musk, sweat, and salivary glands. Exocrine glands in the liver secrete bile. The pancreas has both endocrine and exocrine glands.

11-1 How do endocrine glands differ from exocrine glands?

Endocrine glands secrete tiny amounts of hormones directly into the bloodstream and not through ducts. This feature differentiates them from exocrine glands, which secrete their products onto epithelial surfaces through tiny tubes called ducts.

Describe the process of endocytosis and exocytosis.

Endocytosis - "Going into cell" - plasma membrane involutes, engulfs the particle or liquid, and forms a vesicle by closing the cell membrane around it - Phagocytosis - "Cell eating" - engulfs large particles or entire cells, forming a Phagosome (white blood cell or macrophage) - Pinocytosis - "Cell drinking" - engulfs liquid, uses a small amount of membrane to form Pinocytotic Vesicle, vesicles break down and release liquid into cell (lining of the intestines and renal tubules) - Receptor mediated - specialized protein receptors on membrane bind to ligands specific to receptors. Forms a Coated Pit (hormones, iron, cholesterol) Exocytosis - Excretion of waste products and secretion of manufactured substances -secretary vesicles fuse with membrane and eject contents into the extra cellular space

List and describe the roles of the connective tissues in skeletal muscles

Endomysium - Surrounds each muscle fiber. Fine reticular fibers Perimysium - Binds muscle fibers into fascicles. Composed of reticular fibers and thick collagen fibers Epimysium - Binds groups of fascicles together, outer covering of the entire muscle. Composed of tough collagen fibers All 3 are continuous with the tendons or Aponeurosis that connect muscle to bone or other muscles. (Hold muscles together AND help it attach) Also contain blood vessels, nerve fibers and fat

Where would you find an epiphyseal plate, and what would you find it doing?

Epiphyseal plates (growth plates) are two areas of a long bone that remain as cartilage when an animal is born. Located between the shaft (diaphysis) of the bone and the ends (epiphyses) of the bone, they are the sites where the creation of new bone allows the long bones to lengthen as an animal grows.

5-6 Membranes are composed of what 2 tissue types?

Epithelial and connective tissue

4-1 List three fluid compartments in the body.

Fluid compartments in the body include: intracellular, interstitial, and intravascular.

5-4 How are connective tissue and epithelial tissue similar? How are they different?

Epithelial and connective tissue are similar in that they may be linked to form membranes in the body. Membranes are thin, protective layers that line body cavities, separate organs, and cover surfaces. They are composed of a multicellular epithelial sheet bound to an underlying layer of connective tissue. Unlike epithelial tissue, connective tissue is composed primarily of nonliving extracellular matrix. Although epithelial tissue has no direct blood supply, connective tissue is vascularized; however, the level of vascularity varies among different connective tissue types.

List 7 functions performed by epithelial cells

Epithelial cells (1) protect, cover, and line other tissues; (2) filter biochemical substances; (3) absorb nutrients; (4) provide sensory input; (5) manufacture secretions; (6) manufacture excretions; and (7) act as an interface layer that separates and defines the beginning and ending of different types of tissues.

List the 4 major tissue types

Epithelial tissue Connective tissue Muscle tissue Nervous tissue

List the 4 basic types of body tissue.

Epithelial tissue - is composed entirely of cells, and its main jobs are to cover body surfaces, secrete materials, and absorb materials. Connective tissue - tissue made up of cells and extracellular substances that connect and support cells and other tissues. Muscle tissue - a collection of tissues that support the body and enable it to move, thermoregulate, and transport materials. Some muscles may be controlled voluntarily, whereas others act involuntarily. Examples of involuntary muscle include cardiac and smooth muscle; voluntary muscle includes all of the skeletal muscles. Nervous tissue - A collection of tissues that collect, process, and convey information. Nervous tissue includes the brain, spinal cord, and nerves. Sensory (afferent) nerves convey information about the body's surroundings to the brain, whereas motor (efferent) nerves send instructions from the brain to the body. Some nervous tissues, called mixed nerves, can perform both functions.

5-1 What are the 4 primary types of tissue?

Epithelial, connective, muscle, and nervous

How do the basic actions and purposes of estrogens and progestins differ?

Estrogens are responsible for the physical and behavioral changes that prepare the female for breeding and pregnancy and signal the male that the time for breeding is approaching. Progesterone, the primary progestin, helps prepare the uterus to receive the fertilized ovum and is necessary for pregnancy to be maintained once the fertilized ovum implants in the uterus.

Which type of vision requires more muscular effort: close-up vision or far-away vision? Why?

For close-up vision, the ciliary muscles must contract to take tension off the suspensory ligaments.

How much repeated exposure to loud sounds lead to progressive hearing loss?

Everything up to the generation of an auditory nerve impulse by the hair cells (sensory cells) in the organ of Corti of the cochlea involves movement: the tympanic membrane, the ossicles, the round and oval windows, the endolymph and perilymph in the cochlea, the tectorial membrane, and the microvilli of the hair cells. Loud noises cause exaggerated movements of all those structures. In the short term, irreparable damage rarely results. Over long periods of time, however, loud noises can cause damage to these mechanical structures that the body may not be able to fully repair. Some examples might include damage to the microvilli of the hair cells, thickening or displacement of the tectorial membrane, thickening of the membranes covering the round and oval windows, and damage to the delicate joints between the bony ossicles.

List excitatory and inhibitory neurotransmitters and describe their role in the conduction of nerve impulses

Excitatory - Stimulate the postsynaptic cell to produce an impulse Inhibitory - inhibit the postsynaptic cell from producing a nerve impulse Acetylcholine- Either excitatory or inhibitory depending on its location. - Excitatory between somatic motor neurons and muscles - Inhibitory between parasympathetic nerves and heart (which slows) Norepinephrine - Arousal and fight or flight reactions of sympathetic nervous system Epinephrine - From adrenal medulla - fight or flight hormone of sympathetic nervous system Dopamine - In brain - autonomic functions and muscle control GABA - Inhibitory in brain tranquilization with sedation (reduced anxiety with drowsiness) Glycine - Inhibitory in spinal cord Catecholamines = Norepinephrine, Epinephrine, and Dopamine

What is the difference between an excitatory and an inhibitory neurotransmitter?

Excitatory neurotransmitters have an excitatory effect on the postsynaptic membrane when they combine with their specific receptors. Specifically, excitatory neurotransmitters usually cause an influx of sodium so that the postsynaptic membrane moves toward threshold. If the postsynaptic membrane is stimulated sufficiently by enough excitatory neurotransmitters, threshold will be attained and depolarization of the postsynaptic membrane will occur. In contrast, inhibitory neurotransmitters tend to hyperpolarize the postsynaptic membrane, making the inside of the cell more negative instead of positive and moving the charge within the postsynaptic cell farther away from threshold. When inhibitory neurotransmitters combine with their specific receptors on the postsynaptic side, they may cause chloride channels or potassium channels to open up on the postsynaptic membrane. This allows the negatively charged chloride ions (Cl-) to enter the postsynaptic cell and potassium (K+) ions to leave the cell, making the inside of the cell more negatively charged (a change in charge that is opposite from that needed to reach threshold).

What is the difference between excretion and secretion? These are both examples of what?

Excretion is the movement of waste products from the intracellular to the extracellular environment, and secretion is the movement of manufactured molecules from the intracellular to the extracellular environment. Both are examples of exocytosis.

7-3 Name the skull bones that make up each of these groups: External bones of the cranium Internal bones of the cranium Bones of the ear External bones of the face Internal bones of the face

External bones of the cranium: occipital bone, interparietal bones, parietal bones, temporal bones, and frontal bones Internal bones of the cranium: sphenoid bone and rostral ethmoid bone Bones of the ear: malleus, incus, and stapes External bones of the face: incisive bones, nasal bones, maxillary bones, lacrimal bones, zygomatic bones, and mandible Internal bones of the face: palatine bones, pterygoid bones, vomer bone, and turbinates

What are the 3 basic constituents of connective tissue question month

Extracellular fibers, ground substance, and cells

List the functions of body proteins.

FUNCTIONAL (globular) Chemical reactions - protein enzymes: Central to almost every bio chemical reaction in the body Transport of molecules - hemoglobin transforts oxygen in blood Regulation of metabolism - peptide hormones ( Regulate metabolic activity call my growth, and development) Immune system - antibodies are proteins created by immune cells that recognize foreign substances as viruses STRUCTURAL (fibrous) Structural framework - - Collagen: gives strength to bones, tendons, ligaments. - Keratin: hair, nails, waterproofing of skin Physical movements - - Actin and Myosin: Contractile proteins found in muscle. Actin also used for intercellular transport

How is facilitated diffusion different from simple diffusion? What is the limiting factor in the rate of facilitated diffusion?

Facilitated diffusion requires the assistance of an integral protein or carrier protein located in the bilayer. The number of available carrier proteins limits the rate of facilitated diffusion.

What is the common term for adipose tissue?

Fat

What are fibroblasts and what role do they play in connective tissues?

Fibroblasts are fixed cells. They are large, irregularly shaped cells that manufacture and secrete both the fibers and the ground substance characteristic of their particular matrix. As the cells mature and the matrix is formed, fibroblasts adopt a less active role. If additional matrix is required later, the cells can convert back to the active form.

7-7 What are the main characteristics of fibrous joints, cartilaginous joints, and synovial joints?

Fibrous joints are immovable because the bones are firmly united by fibrous tissue. Examples include joints (sutures) between most bones of the skull. Cartilaginous joints are capable of only a slight rocking movement. Examples include the intervertebral disks between the bodies of adjacent vertebrae in the spine. Synovial joints are freely movable joints such as the shoulder and stifle joints. All synovial joints share some common characteristics, including articular surfaces on the bones, articular cartilage covering the articular surfaces, and a fluid-filled joint cavity enclosed by a joint capsule. Firm connective tissue bands called ligaments may help stabilize the bones and hold the joint together.

On which bone of the pelvic limb is the calcaneal tuberosity found? What is its purpose?

Fibular tarsal bone The fibular tarsal bone is the point of attachment for the gastrocnemius muscle and corresponds to the heel.

What is the relationship between hydrostatic pressure and filtration?

Filtration is based on a pressure gradient. Liquids may be pushed through a membrane if the pressure on one side of the membrane is greater than that on the other side. The force that pushes a liquid is called hydrostatic pressure.

Describe 1st- and 2nd- intention wound repair.

First intention wound repair occurs with wounds whose edges are held in close apposition. These wounds may be superficial scratches or wounds that have been sutured or held closed with special bandages. The skin forms a primary union without the formation of granulation tissue or significant scarring. Second intention wound repair is also known as contraction and epithelialization. The edges of the wound are separated from each other, and the wound is allowed to heal without surgical closure. Granulation tissue forms to close the gap, resulting in scar formation. Third intention wound repair results when the wound is sutured at least 3 to 5 days after the injury. Granulation tissue is present in the wound by this time and helps to control infection and fill the tissue defect.

Describe the structure and locations of sebaceous glands

Found all over the body except in certain specialized regions, such as paw pads and the planum nasale Located in the dermis and may be simple or complex alveolar structures Most sebaceous glands have a single duct the empties into a hair follicle, but others have ducts that empty directly onto the surface of the skin (in mucocutaneous junctions: lips, labia vulvae, penis, prepuce, anus, eyelid, ear canal) In sheep, sebaceous glands Empty directly under the surface of the skin in the infraorbital pouches, interdigital pouches, and inguin pouches. Glands associated with hair follicles are found in the triangle formed by the surface of the skin, the hair follicle, and the arrector pili muscle Sebaceous gland alveoli are lined with epithelial cells that manufacture and store an oily, lipid substance composed primarily of glycerides and free fatty acids. When the cells become full they rupture and release their contents into the center of the alveolus. This white, semi liquid mixture is called SEBUM. In sheep, sebaceous glands produce a substance that ultimately becomes LANOLIN Classified as a holocrine structure because the epithelial cell is lost in the process of secretion Arrector pili muscle contacts and compresses the gland and forces sebum from the alveolus through the duct into the hair follicle, coating the base of the hair.

What are GABA and glycine?

Gamma-aminobutyric acid (GABA) and glycine are inhibitory neurotransmitters. GABA is found in the brain, and glycine is found in the spinal cord.

List the 3 categories of hormones produced by the adrenal cortex

Glucocorticoid Hormones - General hyperglycemic effect (cause blood glucose levels to rise) Mineralocorticoid Hormones - Regulate levels of important electrolyte (mineral salts) in the body Sex Hormones - Male and female (androgens and estrogens) are produced in small amounts, effects are usually minimal

11-5 What 3 groups of hormones are produced in the adrenal cortex? What are their effects?

Glucocorticoid hormones, mineralocorticoid hormones, and sex hormones. Glucocorticoids have a general hyperglycemic effect: that is, they cause the blood glucose level to rise. Mineralocorticoid hormones regulate the levels of some important electrolytes (mineral salts) in the body. The principal mineralocorticoid hormone aldosterone affects the levels of sodium, potassium, and hydrogen ions in the body. Aldosterone's target is the kidney, where it causes sodium ions to be reabsorbed from the urine back into the bloodstream in exchange for potassium and hydrogen ions. Aldosterone also affects water levels in the body, in that water accompanies sodium back into the bloodstream when sodium ions are reabsorbed. The amounts of sex hormones are very small, and their effects are usually minimal.

Other than promoting growth in young animals, what are some of the other effects of GH?

Growth hormone (GH) helps regulate the metabolism of proteins, carbohydrates, and lipids in all of the body's cells. The effect of GH on protein metabolism is to encourage the anabolism, or synthesis, of proteins by body cells. The effects of GH on carbohydrate and lipid metabolism are linked. GH causes the mobilization (release) of lipids from storage in adipose (fat) tissue and their catabolism (breakdown) in body cells for energy production. At the same time, it discourages the cells from using carbohydrates, principally glucose, as energy sources. Because glucose is such an important energy source for the body's cells, a balance between GH and insulin is important to maintain homeostasis of glucose levels in the blood.

11-6 Which four hormones have hyperglycemic effects in the body? What is the only hormone that acts to lower the blood glucose level?

Growth hormone, thyroid hormone, glucocorticoid hormones, and glucagon all serve to increase the level of glucose in the blood. Insulin acts to lower the blood glucose level.

List and describe the components of bone

Hardest and most rigid connective tissue STRUCTURE collagen fibers and calcium salts - lacunae: have osteocytes - canaliculi: extensions of osteocytes - Haversian canals: vascularization and nervous supply FUNCTION support and protect - produce blood - store calcium and other minerals

7-2 What is the difference between a Haversian canal and a Volkmann's canal?

Haversian canals are part of the haversian system of compact bone. They run lengthwise with the bone and consist of a laminated (multilayered) cylinder composed of concentric layers of ossified bone matrix arranged around a central canal. The haversian canal contains the blood, lymph, and nerve supply for the osteocytes. Volkmann's canals are channels through which blood vessels travel to supply bones. They penetrate the periosteum at right angles to the long axis of the bone and at right angles to the haversian canals. The blood vessels in the Volkmann's canals join with the blood vessels in the haversian canals to bring nutrients to the osteocytes in the haversian systems.

Rudolf Virchow

He observed cells and created cell theory

When does the healing process begin?

Healing begins with inflammation.

List the structures that comprise the dermis and describe the function of each

Highly fibrous - Composed of dense irregular connective tissue that contains collagen, elastic, and reticular fibers - Hair follicles, nerve endings, glands, smooth muscle, blood vessels, and lymphatic channels are all found in the dermis - Fibroblasts, adipocytes, and macrophages are present, most common cellular elements - Binds the superficial epidermis to the underlying tissues PAPILLARY LAYER: Thin, superficial layer Loose connective tissue with loosely woven fibers on ground substance Forms nipple-like projections called dermal papillae which rise up into the epidermis and helps cement the epidermis and dermis together and provides more surface area for blood vessels to provide nourishment to the active cells of the stratum basale Contains nerve endings or pain receptors and touch receptors called Meissner's corpuscles (sensitive to light touch), and temperature sensors RETICULAR LAYER Thick, deeper layer Dense, irregular connective tissue, accounts for 80% of the dermis

What is histology?

Histology is the study of the microscopic structures of tissues and organs.

Why do hormone-like drugs generally have a high potential for undesirable side effects?

Hormonelike drugs have a high potential for undesirable side effects because the production and effects of natural hormones are so interrelated, so the therapeutic use of hormones and hormonelike drugs can produce some potent and widespread problems. Also, the amounts of hormones used therapeutically are usually very large compared with the normal physiologic hormone levels in the body; therefore, the potential for undesired side effects increases accordingly. If these drugs are not discontinued gradually, serious side effects can occur.

11-2 What is a hormone?

Hormones are chemical messengers produced by endocrine glands and are secreted directly into blood vessels.

Differentiate between hydrophobic and hydrophilic molecules.

Hydrophobic - molecules that do not mix well in water. Usually electrically neutral, non polar molecules such as lipids - Gather into droplets when added to water - Lipid bilayer tail Hydrophilic - chemicals that dissolve or mix well in water - Usually polar molecules or ions - Lipid bilayer head

If trauma occurs in the segment of the spinal cord through which a particular reflex arc passes, will the reflex arc be hyperreflexive or hyporeflexive?

Hyporeflexive

List the cranial nerves and describe their functions

I Olfactory. S smell II Optic. S vision III Oculomotor M eye movement, pupil size, focusing lens IV Trochlear. M eye movement V Trigeminal. B sensations from head and teeth, chewing VI Abducent. M eye movement VII Facial. B face and scalp movement, salivation, tears, taste VIII Vestibulochochlear S balance, hearing IX Glossopharyngeal. B Tongue movement, swallowing, salivation, taste X Vagus (wanderer) B Sensory from GI tract and respiratory tree - motor to larynx, pharynx, parasympathetic, abdominal, thoracipharyngitis, XI Accessory. M Head movement, accessory motor with Vagus XII Hypoglossal M Tongue movement

List and describe each of the phases of healing

INFLAMMATION Red, swollen, hot, tender. Possible decrease of function. - It's an attempt to isolate the area, limit damage caused by injury, and prevent further damage 1. VASOCONSTRICTION for 5-10 minutes controls hemorrhage. VASODILATION from histamine and heparin next increases blood flow causing heat and redness. also increases oxygen and nutrients 2. fluid from plasma (enzymes, antibodies, and proteins) pours in causing swelling and pain 3. clot formations slows bleeding and isolates wound from invasion of pathogens. fibrinogen is converted to fibrinwhich weaves like a net to support clots 4. macrophages and neutrophils (white blood cells) move through blood vessels and squeeze through capillaries to remove debris and microinvaders. short lives and build up of dead ones is pus. 5. increases blood flow disperses histamine and heparin causing a return of normal capillary size and permeability. blood flow and fluid leakage abate and swelling, heat and redness begin to subside ORGANIZATION formation of granulation tissue REGENERATION

List the locations and actions of muscles of respiration

INSPIRATORY MUSCLES Diaphragm - separates thoracic cavity from abdominal. Convex surface protrudes into thoracic cavity. Flattens with contraction; increases size of thoracic cavity and draws air in External Intercostals - run in oblique direction between ribs. When they contract they rotate ribs a forward and forward; increases size of the rested cavity and draws air in EXPIRATORY MUSCLES Internal Intercostals - run at right angles to external intercostals. When they contract they rotate the ribs backward and push air out of the lungs Abdominal - push abdominal organs against caudal side of diaphram, returns it to its dome shape and decreases size of thorax. Used mainly when breathing fast and hard (exercise)

Describe the negative feedback system that controls the production of hormones

If the activity is DECREASED by rising levels of the hormone it is NEGATIVE feedback Like a heater - gets hot, heater turns off

What effect does a hypotonic solution have on a cell? What passive membrane process causes this effect?

If the extracellular fluid is hypotonic, the inside of the cell contains a higher concentration of solutes than the outside of the cell. In this scenario, water would flow by osmosis into the cell and cause it to swell and possibly burst.

10-5 An animal has an area of inflammation located at the dorsal limbus of its right eye. Where is the lesion located?

If the iris is compared with the face of a clock, this lesion would be at approximately 12 o'clock, at the junction of the cornea and the sclera (white) of the eye.

If the medial rectus muscle of an animal's eye was damaged and it lost its ability to contract, what would the effect be on the positioning of the affected eye? Why?

If the medial rectus muscle were unable to contract, the pull of the lateral rectus muscle would cause the eyeball to deviate (move abnormally) laterally. Also the animal would not be able to rotate that eyeball toward the midline, because this muscle originates from a small area around the optic canal and fissure and inserts on the medial side of the sclera (near the 9 o'clock position if you are standing in front of the animal).

How would an animal with a plugged nasolacrimal system appear? Why?

If the nasolacrimal system were plugged, tears would be "spilling" out of the eyes because they would have nowhere to drain.

5-2 Epithelial tissue Is characterized as simple, stratified, or pseudostratified. What does this mean?

If there is only a single layer of epithelial cells, the tissue is classified as simple. If there is more than one layer of cells, the tissue is called stratified. Pseudostratified columnar epithelium is an epithelial layer that is not truly stratified. The epithelial cells appear to be stratified because the nuclei are found at different levels across the length of the tissue layer. In addition, not all the cells reach the luminal surface; therefore, the cells appear to be at different levels, as though stratified. In reality, each cell forms a distinct attachment, however subtle, with the basement membrane. In this way, pseudostratified columnar epithelium forms a single layer and therefore is considered a simple epithelium.

What 3 pairs of bones make up the pelvis? What region of the pelvis does each form?

Ilium, ischium, and pubis The ilium is the cranialmost bone of the pelvis. It projects upward in a dorsocranial direction and is the bone that forms the sacroiliac joint with the sacrum. The ischium is the caudalmost pelvic bone. The pubis is the smallest of the three pelvic bones. It is located medially and forms the cranial portion of the pelvic floor.

Compare and contrast the structure of DNA and RNA.

In DNA the sugar is deoxyribose, and in RNA the sugar is ribose. In DNA these bases are weakly bonded to nitrogenous bases on an opposing strand. In this way, DNA forms a double-stranded molecule, the basic structure of which is analogous to a twisted ladder in which the vertical poles are composed of alternating sugar and phosphate groups and the horizontal rungs are paired nitrogenous bases. DNA's molecular structure is therefore called the double helix. RNA, however, is a single-stranded molecule that has no opposing strand. The single strand of RNA is similar in structure to each of the strands found in DNA.

Describe the process of depolarization and repolarization of neurons

In its Resting State, The sodium-potassium pump moves sodium ions outside and pumps potassium ions inside. Polarizes the cell membrane. Inside more negative than outside (3 NA+ out. 2 K+ in), called resting membrane potential. DEPOLARIZATION Impulse from adjoining neuron or stimulus causes Sodium Channel to open, allowing NA+ to freely flow in. Changes the inside of the neuron from negative to positive (called an Action Potential) (DEpolarization because of the loss of 2 distinct poles of sodium and potassium on either side of the membrane) REPOLARIZATION Almost immediately the Sodium Channel snap shut and Potassium Channels open. Potassium flows out to lower concentration of K+ outside and to get away from positive charge now in the cell. Causes the cellnto be negative inside again. Close almost immediately. The change in the cell's charge back to the net negative is called Repolarization (sodium and potassium are on opposite sides again

What is the difference between the primary growth center of a bone and a secondary growth center?

In long bones, the primary growth center is a location in the shaft (diaphysis) where bone development begins. Additional growth centers called secondary growth centers develop in the ends (epiphyses) of the bone.

List the hormones produced by the pancreatic islet cells and describe the effects of each

Insulin - causes glucose, amino acids, and fatty acids to be absorbed from blood, through cell membranes, into cells - LOWERS glucose level in blood - Essential for life Glucagon - Stimulates liver to convert glycogen to glucose, and - stimulates to glucooneogenesis (conversion of fat and protein to glucose) - Other hormones have same effects so it is not vital for life - RAISES glucose level in blood Somatostatin - Inhibits secretion of insulin, glucagon, and GH - diminishes activity of the GI tract

What are Integral, Peripheral, and Glycoproteins' location and functions? Add them to your drawing

Integral and peripheral proteins are types of globular proteins. Some integral proteins are located within the bilayer, spanning it. These form selective passageways and pores that permit only particular substances to enter or exit the cell. Some integral proteins are membrane receptors that act as binding sites on the cell's surface. Peripheral proteins are bound to the inside and outside surfaces of the cell membrane and sometimes act as enzymes to catalyze specific chemical reactions. They may also be involved in the mechanics of changing the cell's shape. Glycoproteins, in addition to glycolipids, are the principal components of the "sugar coating" that covers the surface of some cells. This coating is called the glycocalyx.

What is another name for cutaneous membrane?

Integument

Describe the origin of tears and explain how tears flow onto and drain from the eye

Lacrimal Apparatus includes the structures that produce and secrete tears and the structures that drain them from the surface of the eye - Lacrimal glands - produce tears - located dorsal and lateral to each eye inside the bony orbits that protect the eye. Each gland deposits tears in the dorsal conjunctival sacs, then tears wash down over the surface of the eye aided by blinking - Lacrimal Puncta - drains tears away from eyes - two small openings, one on the upper and one on the lower lid, near medial canthus of each eye - Tears flow from two Lacrimal Puncta Ducts to Lacrimal Sacs then down single Nasoacrimal Ducts to the Nasal Cavity

List and describe the anatomic terms of direction.

Left - individual's left Right - individual's right Cranial - toward the head end of the body Rostral - toward the tip of the nose (head only) Caudal - toward the tail end of the body Dorsal - toward the back Ventral - toward the belly Medial - toward the median plane Lateral - away from the medial plane Deep (internal) - toward the center (whole body or part) Superficial (external) - toward the surface (whole body or part) Proximal - toward the body (extremity) Distal - away from the body (extremity) Palmar - "back" of forelimb from carpus distally Plantar - "back" of hindlimb from tarsus distally Dorsal - "front" of forelimb and hindlimb from carpus and tarsus distally

Can you get 3 examples of cells that are transient in connective tissue? Can you describe their form and function?

Leukocytes, mast cells, and macrophages are transient cells in connective tissue. Leukocytes are relatively large and round compared with red blood cells. They can squeeze through the walls of tiny blood vessels to enter the surrounding tissue. This process is called diapedesis. Leukocytes are important members of the defensive immune system. Mast cells are oval cells easily identified by the large number of dark-staining granules stored in the cytoplasm. These granules contain histamine and heparin, potent biochemicals that, when released into the tissue, initiate an inflammatory response. Histamine increases blood flow to the area by making the capillaries leaky, and heparin prevents blood from clotting and ensures that the pathways for increased blood flow remain open. Macrophages are massive, irregularly shaped phagocytizing scavengers that may be either fixed or transient in connective tissue. They engulf microbes, dead cells, and debris that are subsequently digested in the macrophage's lysosomes. Mobile macrophages are drawn to sites of infection or inflammation, where they move aggressively through the affected area to engulf microinvaders. In this way they are an important part of the immune system and help tissues fight infection.

List and describe the four bone shapes

Long - longer than they are wide. Each one has a proximal epiphysis and distal epiphysis consisting of cancellous bone covered by compact bone. Main part is diaphysis, made of compact bone Short - shaped like small cubes or marshmallows. Core of spongy bone covered by thin layer of compact bone -carpal and tarsal bones Flat - thin and flat. Cancellous sandwiched by compact. -Skull, scapulas, pelvic bone Irregular - have characteristics of more than one, or a truly irregular shape -vertebrae, sesamoid bones

Make the following great movements with your own body: abduction, adduction, circumduction, extension, flexion, and rotation

Make the following joint movements with your own body: abduction, adduction, circumduction, extension, flexion, and rotation.

What is the difference between a symport and antiport system?

Many active transport systems move more than one substance at a time. If all the substances are moved in the same direction, the system is called a symport system. However, if some substances are moved in one direction and others moved in the opposite direction, the system is called an antiport system.

List the locations and actions of muscles of the head and neck

Masseter - Cheek area of school, most powerful chewing muscle - closes the jaw Splenius and Trapezius - Dorsal (upper) part of neck. Extend (raise) the head and neck Brachiocephalicus - Large, strap-like muscle that extends from the proximal area of the humerous to the base of the skull. Extends head and neck and pulls front leg forward Sternocephalicus - Small, strap-like muscle that extends from the sternum to the base of the skull - acts to flex (lower) the head and neck. Gravity helps so it doesn't have to be particularly large or strong

What is the matrix of bone made of? What makes it so hard?

Matrix is the intercellular substance in which bone cells are embedded. It is hard because calcium and phosphate crystals are deposited in it.

What are the membrane receptors & ligands and what role do they play in the health of cells? How does obesity affect cell membrane receptors for insulin?

Membrane receptors are integral proteins and glycoproteins that act as binding sites on the cell surface. Some of them play a vital role in cell-to-cell recognition, a process called contact signaling. This is particularly important during cell-mediated immune responses and helps bacteria and viruses find preferred "target" cells. Membrane receptors are also involved in a process called chemical signaling. Hormones, neurotransmitters, and other chemical messengers called ligands bind to specific binding sites on cell surfaces. Once bound to the cell membrane, ligands can bring about a change in the cell's activity. Some ligands act as enzymes to activate or inactivate a particular cellular activity.

Describe the connective tissue layers that surround the brain and spinal cord

Meninges are 3 connective tissue layers that surround the brain and spinal cord - Dura mater - Outermost layer, tough and fibrous Arachnoid - delicate, spiderweb-like Pia Mater - lies directly on the surface of the brain and spinal cord - All 3 contain blood vessels that supply nutrients and oxygen to the brain and spinal cord - Fluid, fat, and connective tissue between layers of the meninges provide cushioning and distribution of nutrients

Can you describe merocrine, apocrine, and holocrine glands? How do they differ from one another?

Merocrine glands: The majority of glands package their secretions into granular units and release them via exocytosis as they are manufactured. In merocrine glands, the secretory cells remain undamaged during secretion. Secretion in apocrine glands involves the loss of the apex of the secretory cell. Apocrine glands: The secretory cells in apocrine glands do not release their granules as they are manufactured. Instead they store the granules until the apex of the cell is full, at which point the cell pinches in two and the top part (the apex) is released into the duct system. Later, the cell repairs the damage and repeats the process. Holocrine glands: Holocrine glands also store granules in the secretory cells until they are needed. However, in holocrine glands the entire secretory cell is destroyed in the act of releasing its secretory product. The subsequent degeneration of the cell allows the release of the granules.

What is the term for mRNA formation?

Messenger RNA (mRNA) formation is known as transcription, which occurs in the nucleus.

Differentiate between microscopic and macroscopic anatomy.

Microscopic anatomy - is the study of anatomic parts too small to be seen with the unaided eye, such as cells and tissues. Macroscopic anatomy - is also called gross anatomy; the study of body parts large enough to be seen without magnification, such as lung, leg, or brain.

Why do some epithelial cells have cilia and microvilli? What role do they play? Where are the cells with these specialized surfaces found in the body?

Microvilli increase the surface area of cells and allow more absorption and secretion. They are found on epithelial cells in the intestines and urinary tract. Cilia are found on the free surfaces of cells, usually in the respiratory and urogenital tracts. Ciliary movement occurs in coordinated "beats" that enable the efficient transport of material. In the trachea, cilia help propel mucus and debris up and away from the lungs toward the mouth. In the uterine tube, the beating motion of cilia encourages newly released ova into the oviduct, or infundibulum.

By which mechanism of bone formation do most bones in the animal body develop before birth, and how does the process take place?

Most of the bones in the body develop by the endochondral method, in which the body first creates a cartilage template that is subsequently replaced by bone. Most bones start out as rods of cartilage in the developing fetus. These cartilage rods are prototypes of the bones that will eventually replace them.

Which are afferent nerve fibers: motor nerve fibers or sensory nerve fibers? Which are efferent?

Motor nerves are efferent and sensory nerves are afferent

Where are mucous membrane found? What functions do they perform?

Mucous membranes, or mucosae, are always found lining the organs with connections to the outside environment. These organs are part of the digestive, respiratory, urinary, and reproductive tracts and include the mouth, esophagus, stomach, intestines, colon, nasal passages, trachea, bladder, uterus, and others. With the exception of the mucosae of the urinary tract, mucosae in general can produce large quantities of protective and lubricating mucus. Goblet cells or multicellular glands may be found throughout the tissue. These structures are responsible for the production and secretion of mucus, which consists primarily of water, electrolytes, and a protein called mucin. Mucus is slippery and therefore can decrease friction and assist with the passage of food or waste. Because of its rich supply of antibodies and its viscous consistency, mucus is also helpful in the entrapment and disposal of invading pathogens and foreign particles. This is particularly apparent in the nasal passages, where microorganisms and debris are inhaled and trapped by mucus. Some mucosae can also absorb as well as secrete. For example, the epithelial layer in the intestine is specially designed for rapid and efficient transfer of nutrient molecules from the intestinal lumen to the underlying connective tissue and its blood supply. The mucosa therefore plays an important role in monitoring and controlling what enters the body, and mucous membranes form an important barrier between the outside environment and the delicate inner workings of the body. The secretory and absorptive qualities of mucosae make them particularly well suited for this role.

In general, how are multicellular exocrine glands constructed?

Multicellular exocrine glands are made up of two distinct components, a secretory unit in which secretions are produced by secretory cells and a duct that carries the secretion to the deposition site. In most glands the secretory unit is surrounded by connective tissue rich in blood vessels and nerve fibers. It not only nourishes the secretory unit but also provides structural support and may extend into the gland to form distinct lobes. In some exocrine glands the secretory unit is surrounded by contractile cells called myoepithelial cells that assist with the discharge of secretions into the glandular duct.

Where does protein synthesis begin?

Protein synthesis begins in the nucleus with transcription and ends in the cytoplasm with translation.

How are the functions of neurons and neouroglia different from each other?

Neurons are the basic functional units of the nervous system. That is, they are the smallest pieces of the system that show basic nervous system functions, such as responding to stimuli and conducting impulses from one part of the cell to another. The neuroglia, or glial cells (from the Greek glia, meaning "glue"), structurally and functionally support and protect the neurons. They outnumber neurons about 10 to 1, but they are not directly involved in the transmission of information or impulses through the nervous system. Rather, they are important parts of the infrastructure necessary for the neurons to do their jobs.

With which branch of the autonomic nervous system are muscarinic and nicotinic receptors associated?

Nicotinic acetylcholine receptors are found primarily on the postganglionic neurons of both the sympathetic and parasympathetic nervous systems. Muscarinic cholinergic receptors are found on the target organs and tissues supplied by the postganglionic neuron of the parasympathetic nervous system.

An animal can intentionally blink its eyelids. Can it intentionally cover its eye with its 3rd eyelid? Why or why not?

No muscles attach to the third eyelid. Its movements are entirely passive.

Are only organic compounds necessary for life?

No. Both organic and inorganic compounds are necessary for life on earth.

Is interphase a time when the cell is resting? Why or why not?

No. Interphase is a period of intense metabolic activity in the cell. Before each cell can divide, a perfect copy of the DNA must be created to pass on to the daughter cells. This replication of DNA occurs during interphase. In addition, all of the enzymes and other proteins needed to drive cell division must be created during interphase.

What is nocioception and what roles do transduction, transmission, modulation, and perception play in it?

Nociception is the process of experiencing pain. Transduction is the conversion of the painful stimulus to a nerve impulse that occurs at the sensory nerve ending. Transmission of the nerve impulse up the sensory nerve fibers to the spinal cord is the next step. Modulation (changing) of the sensory nerve impulses can occur in the spinal cord, and this can significantly influence the information the brain receives, particularly in cases of chronic and/or severe pain. This modulation process can amplify (make more severe) or suppress (make less severe) sensory impulses through synapses between neurons in the dorsal horns of the spinal cord. Finally, perception of the painful impulses by several areas of the brain occurs. Conscious perception occurs in the cerebral cortex, but other areas of the brain are also involved. These include areas involved with the autonomic nervous system (fight or flight), fear and anxiety, memory, arousal, and behavior and emotion.

List and describe the processes that contribute to nocioception

Nocioception = pain sensation Nociocepters = pain receptors 1. Transaction - conversion of painful stimulus to a nerve impulse (at sensory nerve ending) 2. Transmission - nerve impulse travels up the sensory nerve fibers to the spinal cord 3. Modulation - can occur in spinal cord - Can significantly influence the information the brain receives, particularly with chronic or severe pain. - Can amplify or suppressed impulses through synapses between neurons in the dorsal horns of the spinal cord 4. Perception - in several areas of brain Conscious perception in cerebral cortex, also autonomic nervous system (fight or flight), fear, anxiety, memory, arousal, and behavior and emotion

List the parts that make up the nucleus; for each part, explain its structure and function.

Nucleus - wide variety of shapes, sizes and numbers. Contains nucleoplasm, DNA, rRNA, and ribosomal subunits. - Site of transcription and production of ribosomal subunits Nuclear envelope - double layered membrane with nuclear pore complexes. Outer membrane continuous with ER - Separates nucleus from cytosol; restricts movements of molecules in and out Chromatin - located in nucleoplasm. Composed of nucleosomes (DNA and 8 histones) connected by linker DNA. Arranged in loose strands - DNA portion contains sequence codes for proteins, and enzymes that control molecular interactions. Supercoils to form X-shaped chromosomes during cell division Nucleolus - dense cluster of ribosomal RNA and protein, not membrane bound - Location of synthesis of ribosomal subunits

Describe the process of intramembranous bone formation

Occurs only in certain skull bones by ossifying the soft membranes surrounding the brain of a developing fetus. Creates the flat bones of the cranium

4-4 Of the thousands of different proteins that a cell could make, how many does it actually produce? Why?

Of approximately 100,000 proteins that a cell could make, it makes only a few hundred because cells have different functions. The number of proteins made depends on the function of the cell.

What stimulates the continued release of prolactin during lactation?

Once lactation begins, prolactin production and release by the anterior pituitary gland continue as long as the teat or nipple continues to be stimulated by nursing or milking.

Differentiate between organic and inorganic compounds.

Organic compounds contain carbon while inorganic compounds do not. Organic - large, complex molecules that contain CC or CH covalent bonds - proteins, carbohydrates, triglycerides, nucleic acids Inorganic - small, often have ionic bonding, rarely contain carbon, no CC or CH bonds - water, salts, acids, bases

What is the relationship between solutes and osmolality?

Osmolality is a measurement of the concentration of solute in fluid. As the concentration of solute increases (or decreases), so too does the osmolality. In other words, fluids that have a high concentration of solutes have a high osmolality.

What is the difference between ossicles and otoliths?

Ossicles are small bones in the middle ear that conduct sound waves from the tympanic membrane to the oval window of the cochlea. Otoliths are tiny calcium carbonate stones in the vestibule that respond to gravity to provide information about the position of the head.

List the cell types that comprise bone and describe the function of each cell type

Osteoblasts - form bone Osteocytes - embedded in the bone matrix, can revert to Osteoblasts in case of injury Osteoclasts - eat away at bone. Allow body to withdraw calcium

What are otoliths and why are they important to the equilibrium sense?

Otoliths are tiny crystals of calcium carbonate in a gelatinous matrix that covers hair cells and supporting cells of the macula. The hair cells are similar to the hair cells of the organ of Corti in the cochlea. Gravity causes the otoliths and the gelatinous matrix to put constant pressure on the hairs as long as the head stays still. Movement of the head bends the sensory hairs, which generate nerve impulses that give the brain information about the position and linear movement of the head. Otoliths are important to the sense of equilibrium because information sensed by the vestibule (which contains the otoliths) regarding linear motion and head position is integrated with information about rotary motion of the head gained by the semicircular canals so that the brain can form a picture of what is happening to the animal's head, and by extension, to its body as a whole. Together, the vestibule and semicircular canals provide the total picture of equilibrium to the brain.

Describe the molecular structure of the cell membrane.

Phospholipid bilayer - Hydrophilic heads on outside, hydrophobic lipid tales on the inside Thin - 60 to 100 angstroms Proteins suspended in bilayer move easily throughout membrane, creating a changing pattern, creating fluid mosaic Lipid soluble passes through easily, ionized and water soluble don't - amino acids, sugars, proteins Cholesterol between phospholipids stabilizes it, keeps it fluid, adds to the oily nature of the internal layer Integral proteins - span membrane, some are channel proteins Glycocalyx - covers outside, important in cell recognition, contact signaling and cell mediated immunity - includes cell adhesion molecules (CAM) and receptors Rafts - organized functional areas on cell surface - rigid area of phospholipids, cholesterol, and protein

List and describe the 3 types of hair

Primary or guard hairs: Generally straight or arched and are thicker and longer than secondary hairs. They are the predominant hairs in a complex hair follicle (one primary surro I need bh numerous secondary). Secondary or wool type hairs: Softer and shorter than primary hairs. Generally wavy or bristled in dogs and are the predominant hair type in species with wool-type coats. Tactile or sinus hairs: Used as probes and feelers. They are well supplied with sensory endings that make them particularly sensitive to the slightest bending or touch. Commonly known as whiskers and can be found around the mouth and on the muzzle of many species, as well as mixed throughout the hair coat Also known as sinus hair because of a large blood sinus located in the connective tissue portion of the follicle hair

Differentiate between prime mover, antagonist, synergist, and fixator muscles

Prime Mover (agonist) - Muscle or muscle group that directly produces a desired movement Antagonist - Muscle or muscle group that directly opposes the action of an agonist. - Can help smooth out movements or contract at the same time and produce rigidity and lack of motion Synergist - Skeletal muscle that contracts at the same time as an agonist and assists in carrying out its action Fixator - Stabilizes joints to allow movement to take place (each muscle can be all four at different times)

What is the difference between a prokaryote and a eukaryote?

Prokaryotes do not contain nuclei. Eukaryotic cells have a distinct nucleus in which the DNA has combined with protein to form chromosomes. These, in turn, are surrounded by a protective nuclear envelope.

Differentiate between prokaryotic and eukaryotic cells.

Prokaryotic - no nucleus or membrane-bound organelles Eukaryotic - nucleus and membrane-bound organelles (DNA has combined with protein to form chromosomes)

List the phases of mitosis and describe the events that occur in each phase, draw diagrams.

Prophase - Chromatin, which is normally invisible and spread thinly throughout the nucleoplasm, condenses, coils, super coils and forms discrete X shapes visible under a light microscope. The formation of duplicate chromosomes is essential for life and enables the cell to divide its genetic material equitably for a new generation, without tangling or breaking the long delicate chains of genetic code The X shaped chromosomes are composed of 2 identicle chromatids linked together at a constriction in their middle known as the centromere or kinetochore Cytoplasm becomes more viscous as microtubules from the cytoskeleton are disassembled and the cell becomes round Two pairs of centrioles form anchors on which new microtubules are constructed, and as the microtubules lengthen they push the centrioles further and further apart. In this way a mitotic spindle is formed that provides the structure and machinery necessary to separate the chromosomes Because transcription and protein synthesis cannot occur while the DNA is tightly coiled, the appearance of chromosomes marks the cessation of normal synthetic processes. Prophase concludes with the disintegration of the nuclear envelope Metaphase - The lining up of chromosomes in the exact center of the spindle, known as the equator. The chromosomes are evenly spread apart and form what is called the metaphase plate midway between the poles of the cell. The centromere of each chromosome is attached to a single spindle fiber Anaphase - the centromere of each chromosome splits in half and each single strand becomes its own independent chromosome. As each spindle fiber shortens, the spindle as a whole separates and the single stranded chromosomes are pulled away from their mate towards opposite poles. Each strand takes on a V shape as they are dragged by their mid point toward the centrioles at opposite ends of the cell. The cell elongates dramatically, changing the shape of the cell. The cytoplasm constricts around the plane of the metaphase plate as though forming a waist. Shortest phase of mitosis and usually last only a few minutes. Telophase - Begins when chromosomal movement stops. When the chromosomes reached the pole they begin to unravel, elongate, and return to the diffuse thread-like form characteristic of chromatin. A nuclear envelope appears around each new set of chromosomes. RNA, protein, and ribosomal subunits combine into discrete regions within the new nucleus, reestablishing nucleoli. Microtubules Set made up the spindle disassemble and a ring of peripheral micro filaments begins to squeeze the cell into 2 parts eventually pinching the cell in half and forming 2 daughter cells. Cytokinesis - The process of cytoplasmic division, which marks the end of cell division. The daughter cells immediately enter interphase and begin metabolic activity and growth

What are the four stages of the mitotic phase?

Prophase, metaphase, anaphase, and telophase

Why is the propioception sense so important to the maintenance of balance and an upright posture?

Proprioception allows animals to perform such basic functions as procuring food and escaping danger so they can survive. Maintenance of balance and an upright posture is essential to these activities.

Why are prostaglandins referred to as tissue hormones?

Prostaglandins are sometimes called tissue hormones because they travel only a short distance from where they are produced as opposed to hormones, whose effects occur at a longer distance from where they are produced.

Describe the four anatomic planes of reference.

Sagittal plane - a plane that runs the length of the body and divides it into left and right parts that are not necessarily equal halves. Median plane - a special kind of sagittal plane that runs down the center of the body lengthwise and divides it into equal left and right halves. It could also be called a midsagittal plane, but that term is not commonly used. Transverse plane - a plane across the body that divides it into cranial (head-end) and caudal (tail-end) parts that are not necessarily equal. Dorsal plane - a plane at right angles to the sagittal and transverse planes. It divides the body into dorsal (toward the animal's back) and ventral (toward the belly) parts that are not necessarily equal. If an animal stands in water with its body partially submerged, the surface of the water describes a dorsal plane. In humans, this plane is called the frontal plane.

What is the anatomical name for the shoulder blade?

Scapula

7-5 Name the bones of the thoracic limb from proximal to distal

Scapula, humerus, ulna, radius, carpal bones, metacarpal bones, and phalanges. Some species also have sesamoid bones.

Describe the components of a reflex arc.

Sensory receptor - detects change in environment or body, sends signals To: Sensory neuron - passes signal to spinal cord or brain stem To: Interneurons- integrate incoming sensory impulse with other impulses from other sensory neurons To: Motor neurons - integrated response is sent out from brain or spinal cord to the target organ (muscle or endocrine gland)

How are serous and mucous secretions different?

Serous secretions are watery and contain a high concentration of enzymes, whereas mucous secretions are thick, viscous, and composed of glycoproteins. Secretory cells that manufacture both types of secretions are common in the digestive and respiratory tracts. Mixed exocrine glands contain both mucous and serous components.

List the 3 types of muscle and describe the general characteristics of each type

Skeletal: moves bones, generates heat. multiple nuclei. striated. long, thin fibers. nerve supply is necessary. voluntary control. Cardiac: pumps blood. single nuclei. striated. branched cells. nerve supply modifiesactivity, not necessary for function. multi-unit=necessary for function. involuntary control. Smooth: produce movements in internal organs and structures. single nuclei. no striations. spindle cell shape. visceral-modifies activity, not necessary for function. involuntary control.

Why are cells not the size of watermelons?

Smaller cells have smaller nutritional requirements than large cells but have a proportionately larger surface through which they can absorb the substances they need. Thus smaller cells are able to complete their metabolic functions more rapidly and efficiently than large cells. If cells were the size of watermelons, they would not be able to take in nutrients fast enough to feed themselves and would die. A second limiting factor in cell size is related to the governing capability of the nucleus. A single nucleus can control the metabolic activity of a small cell better than it could a large one. Also, the more active a cell is, the greater its metabolic needs. Therefore, it is not surprising that very large cells or cells that are more active, such as cardiac and skeletal muscle cells, have two or more nuclei.

8-6 Describe a smooth muscle cell in terms of its size, shape, number of nuclei, and appearance under a microscope

Smooth muscles are small and spindle shaped. They are not striated nor are they voluntary. They would be classified as involuntary, nonstriated muscles. They have one nucleus per cell.

What are the principle ions involved in maintaining a cell's resting membrane potential?

Sodium and potassium

Is there a normally higher concentration of sodium inside or outside the cell? Where is there a higher concentration of potassium?

Sodium is 10 to 20 times higher outside the cell than it is inside. Potassium is 10 to 20 times higher inside the cell than outside.

9-8 What are the differences between an autonomic reflex and a somatic reflex?

Somatic reflexes involve contraction of skeletal muscles. Autonomic reflexes regulate smooth muscle, cardiac muscle, and endocrine glands.

Give specific examples of solutes in the body.

Specific examples of solutes include: large molecules such as soluble proteins, phospholipids, cholesterol, and triglycerides and also smaller electrolytes such as sulfate, hydrogen phosphate, chloride, bicarbonate, magnesium, calcium, potassium, and sodium.

What are the 3 basic shapes of epithelial cells?

Squamous, cuboidal, and columnar

Describe the events that occur in skeletal muscle cells during muscle contraction and relaxation

Step 1 (Contraction) At the neuromuscular junction, ACh released by the synaptic terminal binds to receptors on sarcolemma. Step 2 (Contraction) The resulting change in the transmembrane potential of the muscle fiber leads to the production of an action potential that spreads across the entire surface of the muscle fiber and along the T-tubules. Step 3 (Contraction) The sarcoplasmic reticulum releases stored calcium ions, increasing the calcium concentration of the sarcoplasm in and around the sarcomeres. Step 4 (Contraction) Calcium ions bind to troponin, producing a change in the orientation of troponin-tropomyosin complex that exposes active sites on the thin filaments. Cross-bridges form when myosin heads bind to active sites on actin. Step 5 (Contraction) The contraction begins as repeated cycles of cross-bridge binding, pivoting, and detachment occur, powered by the hydrolysis of ATP. These events produce filament sliding, and the muscle fiber shortens. Step 6 (Relaxation) ACh is broken down by AChE, ending action potential generation in the sarcolemma. Step 7 (Relaxation) The sarcoplasmic reticulum reabsorbs calcium ions, and the concentration of calcium ions in the sarcoplasm declines. Step 8 (Relaxation) When calcium ion concentrations approach normal resting levels, the troponin-tropomyosin complex returns to its normal position. This change re-covers the active sites and prevents further cross-bridge interaction. Step 9 (Relaxation) Without cross-bridge interactions, further sliding cannot take place, and the contraction ends. Step 10 (Relaxation) Muscle relaxation occurs, and the muscle returns passively to its resting length.

What is the difference between a sternal rib, an asternal rib, and a floating rib?

Sternal ribs join the sternum and make up the cranial part of the thorax. The ribs that join the adjacent costal cartilage are called asternal ribs and make up the caudal part of the thorax. The cartilage of the last rib or two on each side may not join anything at all and just end in the muscles of the thoracic wall. These nonattached ribs are called floating ribs.

Describe the stretch reflex, withdrawal reflex, crossed extensor reflex, palpebral reflex, and pupillary light reflex

Stretch reflex - (Doctor tap) - A simple, monosynaptic or two-neuron reflex arc, because it involves only a sensory neuron and a motor neuron (with only one synapse between them) without any interneurons The sensory receptor is a specialized structure in the muscle called the Muscle Spindle. If a muscle is stretched the muscle spindle also stretches and sends impulses through the somatic sensory neuron to the spinal cord. Somatic sensory neuron -> spinal cord -> motor neuron in same muscle: causes it to contract At the same time, branches off the sensory neuron will synapsenwith another reflex arc to cause the opposing muscles to relax Withdrawal reflex - Also called the flexor reflex. Happens when you rapidly withdraw a limb or flex the joints after accidentally touching a hot stove or stepping on a sharp object with your bare foot - A strong stimulus to a receptor causes the sensory somatic neuron to send impulses to the spinal cord. Unlike the simple stretch reflex, the withdrawal reflex involves synapses with several interneurons. - Some pull the limb way from the painful stimulus, others inhibit the opposing muscle groups so the withdrawal is rapid and complete. - This reflex can be complicated because many different muscle may be involved in the withdraw from the painful stimulus. - Even though the reflex arc may involve several interneurons, several motor neurons, and several different segments of the spinal cord, it occurs without the brain being aware of the incident until it has already moved Crossed extensor reflex - When the withdrawal reflex Ark. Is stimulated, the a fare and somatic sensory neuron also snaps as with another set of interns because extensor muscles in the opposit leg to contract and support the full weight of your body when the other leg flexes - When the withdrawal reflex arc is stimulated, the afferent somatic sensory neuron also synapses with another set of interneurons that cause extensor muscles in the opposite leg to contract and support the full weight of your body when the other leg flexes. - Called the crossed extensor reflex because the afferent sensory impulse crosses to the other side of the spinal cord and stimulates the muscles that extend the opposite limb - contralateral reflexes - Reflects is that start on one side and travel to the opposite side of the body - ipsilateral reflexes - The stimulus and response are on the same side of the body, like the stretch reflex Palpebral reflex - Receptors on the eyelid margins travels through sensory neurons in CN V to the pons (brain stem), synapses with neurons in the pons (brain stem) then travels through CN VII to the muscle that blink the eyelids. - When active, a light tap on the medial canthus of the eye (the medial corner of the eye where the top and bottom eyelids meet) produces a blink of the eyelids. - When the animal is anesthetized the neurons in the pons become less responsive and the palpable reflects also becomes less responsive - Indicates depth of anesthesia Pupillary light reflex A reflex arc that includes the retina (light sensing layer of the eye), the optic nerve (CN II), neuron clusters in the Diencephalon of the brain, and motor neurons of CN III (which supply the muscle of the Iris that constricts the size of the pupil) Normal response for shining a light in the eye is for the Iris in both eyes to constrict, making the people smaller. Because shining a light in one eye causes a constriction in both eyes, the reflex Ark. Must cross over to the other side of the body. By examining the PLRs in both eyes you can evaluate each reflects arc and identify whether in animal has a visual problem in the retina, the optic nerve, or the motor nerve

If a dog walks out of an air conditioned house and lies in the Sun on a hot summer day, which of its temperature receptors will signal the brain 1st that the dog is getting hot: superficial receptors or central receptorsm

Superficial receptors

Describe the series of events that scientists believes led to the formation of the first cells on earth.

The first cells are thought to have evolved in the massive oceans of our primitive Earth about 3 billion years ago. Jolted by the fierce electrical energy from frequent lightning storms and by the intense, unabated radiation from the sun, the three molecules (methane gas [CH4], water [H2O], and ammonia [NH3]) that made up the primitive atmosphere were forced to collide and split apart. The first organic molecules, similar to amino acids, are thought to have formed in this tempestuous environment. Clustering into heavy droplets, these molecules are believed to have been washed by driving rains from the atmosphere into the warm, shallow seas below. There, proteins, lipids, and carbohydrates evolved and arranged themselves over time into sophisticated, organized structures—the first cells.

What are the names of the 1st two cervical vertebrae and what are their distinguishing characteristics?

The first cervical vertebra, the atlas, holds up the head. It has two large winglike transverse processes (called the wings of the atlas) that can be palpated just behind the skulls of most animals. The atlas is unique in that it has no vertebral body. It consists only of the bony ring the spinal cord passes through and two wings sticking out laterally. The second cervical vertebra, the axis, has a large bladelike spinous process that projects upward dorsally and a peglike dens that fits into the caudal end of the atlas to help form the atlantoaxial joint.

What is the difference between the absolute and the relative refractory periods?

The neuron is said to be in a refractory period because it is refractory or insensitive to new stimuli until it recovers from the previous nerve impulse. During this period, the neuron cannot respond to cause a second depolarization. The absolute refractory period is the period of sodium influx and early potassium outflow when no stimulus of any intensity can cause the cell to depolarize again. The cell absolutely cannot respond. The relative refractory period is the period toward the end of repolarization when it may be possible to stimulate depolarization if a stimulus is very large relative to a "normal" stimulus.

What is the functional relationship between a neurotransmitter and a receptor? Will any neurotransmitter simulate any receptor?

The neurotransmitter molecules released by the synaptic knob bind with receptors and trigger a change in the postsynaptic cell. However, the postsynaptic membrane receptors are very specific about which neurotransmitters they will bind. If the neurotransmitter and receptor are not matched, they will not bind to each other, and no change will be triggered in the postsynaptic cell. Thus synaptic transmission is only effective if receptors to the neurotransmitter exist on the postsynaptic cell's membrane.

Describe the nuclear envelope. How does it differ from the cell membrane?

The nuclear envelope is composed of a lipid bilayer. The outer layer of the nuclear envelope is continuous with the endoplasmic reticulum. More than 10% of the nuclear surface consists of nuclear pore complexes—places where the two layers of the nuclear envelope have fused to form a channel. Although the nuclear envelope is similar in structure and composition to the cell membrane, passage of molecules into the nucleus is less selective because the nuclear pore complexes are relatively large (0.1 nm in diameter).

What is the significance of the nucleolus? What happens in that region of the nucleus?

The nucleoli are regions in the nucleoplasm where there are accumulations of ribosomal RNA (rRNA) and collections of ribosomal subunits. Each ribosome is composed of two different subunits. These ribosomal subunits are exported separately from the nucleus and assembled in the cytoplasm to form functional ribosomes. In addition, nucleoli contain the DNA needed to synthesize rRNA.

What are the nucleotides found in DNA? RNA?

The nucleotides found in DNA are adenine (A), cytosine (C), guanine (G), and thymine (T). The nucleotides found in RNA are adenine (A), cytosine (C), guanine (G), and uracil (U).

Why is the nucleus considered the "CEO of operations"?

The nucleus is considered the "CEO of operations" because its primary function is to house the inherited instructions for making all of the protein needed by the organism. The type of enzyme produced by the cell determines its metabolic activities and function. The hereditary information (DNA) is duplicated prior to cell division so that each daughter cell is given an identical copy of the instructions to make all of the types of protein needed by the cell.

Why is the pituitary gland referred to as the master endocrine gland?

The pituitary gland is often called the master endocrine gland because many of its hormones direct the activity of other endocrine glands.

Where is the pleura found? The peritoneum?

The pleura is found in the thoracic cavity and the peritoneum is in the abdominal cavity.

What is the genetic basis of cellular differentiation?

The position of genes in chromosomes determines the genetic basis of cellular differentiation. Some genes may be located on a region of the chromosome that is available for transcription, whereas other genes may be located inside the molecule and cannot be reached by transcription molecules. We say that one gene is "turned on" while the other gene is "turned off." Genes can be turned off permanently or temporarily. Chromosomes are dynamic in their ability to twist, so that a gene that was once inaccessible on the inside can be moved to the outside of the molecule for use. Differentiation involves the temporary or permanent inhibition of genes that may be active in other cells.

During repolarization, what ion channels open and what ion moves? Where does it move?

The potassium channels open and potassium moves out of the cell.

How would an animal probably feel if they had a middle ear infection that caused the opening of the eustachian tube to swell closed?

The purpose of the eustachian tube is to equalize the air pressure on the two sides of the tympanic membrane. With an infection that closes it off, this could not happen and would cause pain as the membrane bulges in and out, because the tympanic membrane has many pain receptors.

Compare and contrast the sympathetic and parasympathetic nervous systems. Include in your comparison the preganglionic and postganglionic neurons; the origin of preganglionic neurons; the neurotransmitters; and each system's impact on the heart, GI tract, blood vessels, bronchiole diameters, and the size of the pupil of the eye

The sympathetic nervous system emerges from the thoracolumbar area. The parasympathetic system emerges from the brain and the sacral vertebral regions and therefore is called the cranial-sacral system. Outside the thoracolumbar area of the spinal column are a series of autonomic ganglia (many ganglions) that form a chain called the sympathetic ganglion chain. The sympathetic preganglionic neuron extends out from the spinal cord and either synapses with a neuron within the ganglion chain or passes through the ganglionic chain and synapses with a neuron located beyond the sympathetic chain. Each sympathetic preganglionic neuron usually synapses with many postganglionic neurons in a wide variety of locations in the sympathetic chain or in ganglions outside the sympathetic chain. The sympathetic postganglionic neuron extends the remaining distance to the target organ. The parasympathetic preganglionic neuron travels directly from the CNS to its target organ, where it synapses with a short postganglionic neuron in the target organ. Thus the parasympathetic preganglionic neuron is relatively long compared with the very short postganglionic neuron. The sympathetic nervous system primarily uses norepinephrine as its key neurotransmitter. The neurons associated with the parasympathetic nervous system secrete acetylcholine as their neurotransmitter. Heart rate: increased by sympathetic and decreased by parasympathetic system Force of heart contraction: increased by sympathetic; no significant effect from the parasympathetic system Diameter of bronchioles: increased (dilated) by sympathetic and decreased (constricted) by parasympathetic system Diameter of pupil: increased (dilated) by sympathetic and decreased (constricted) by parasympathetic system Gastrointestinal motility, secretions, and blood flow: decreased by sympathetic and increased by parasympathetic system Diameter of skin blood vessels: decreased by sympathetic system; no significant effect from parasympathetic system Diameter of muscle blood vessels: increased by sympathetic system; no significant effect from parasympathetic system Diameter of blood vessels to kidney: decreased by sympathetic system; no significant effect from parasympathetic system

9-7 Which part of the autumn moments nervous system is responsible for the fight or flight response and which is responsible for the rest and restore system?

The sympathetic nervous system is responsible for the fight-or-flight system and the parasympathetic nervous system is responsible for the rest-and-restore system.

9-4What role do the synaptic cleft, presynaptic neuron, neurotransmitter, and postsynaptic neuron play in the continuation of a depolarization wave from one nerve to another?

The synapse is the junction between two neurons or a neuron and a target cell. The synapse consists of a physical gap between the two cells called the synaptic cleft. The neuron bringing the depolarization wave to the synapse and releasing the chemical to stimulate the next cell is called the presynaptic neuron. The chemical released by the presynaptic neuron is called the neurotransmitter, and the neuron that contains the receptors that receive the neurotransmitter is the postsynaptic neuron. In this way, depolarization continues from one cell to the next.

What molecules are more likely to diffuse into a cell? What three principles are involved?

The three principles that enable molecules to diffuse into a cell are: 1. Molecular size: Very small molecules, such as water (H2O), may pass through cellular membrane pores (approximately 0.8 nm in diameter), but larger molecules, such as glucose, cannot. 2. Lipid solubility: Lipid-soluble molecules (e.g., alcohol and steroids) and dissolved gases (e.g., oxygen [O2] and carbon dioxide [CO2]) can pass through the lipid bilayer with ease, whereas other molecules may not. 3. Molecular charge: Ions are small, but their charge prevents easy passage through the membrane pores. Specialized pores called channels selectively allow certain ions to pass through but not others.

Describe the three types of endocytosis.

The three types of endocytosis are phagocytosis, pinocytosis, and receptor-mediated endocytosis.

What are the 3 types of muscle and what are some of the general characteristics of each type?

The three types of muscle are skeletal, smooth, and cardiac. Skeletal muscle is controlled by the conscious mind and moves the bones of the skeleton. Smooth muscle carries out most of the unconscious, internal movements of the body. Cardiac muscle is found only in the heart and makes up the structure of the heart.

If you insert a hypodermic needle into a horse's muscle to give an injection, which end of the needle (tip or hub) is located deep in the muscle and which end is located superficially?

The tip is deep and the hub is superficial.

10-7 How might examination of the bulbar and palpebral portions of the conjunctiva be useful as part of the overall physical examination of an animal?

The transparency of the conjunctiva allows the underlying tissues to show through, so it can be used as a window to see the blood vessels that are hidden elsewhere in the body by opaque structures, such as the skin. By looking through the conjunctiva at the lining of the eyelid, we can often detect abnormalities such as anemia (pale color caused by decreased blood flow), jaundice (yellowish color), and cyanosis (dark purplish color).

5-5 Connective tissue is divided into 2 broad categories. What are they?

The two broad categories of connective tissue are connective tissue proper and specialized connective tissue.

4-3 What are the two major periods that comprise the life cycle of the cell?

The two major periods of the cell's life cycle are: interphase, when the cell is growing, maturing, and differentiating; and mitotic phase, when the cell is actively dividing.

For a second what is the role of the upper CNS in the reflex arc? If the CNS influence is removed or blocked, do reflexes become hyporeflexive or hyperreflexive?

The upper CNS normally produces a dampening or inhibitory effect on the reflex arc. If it is removed, the reflex becomes hyperreflexive.

List the components of the ventral body cavity.

The ventral body cavity is much larger than the dorsal one. It contains most of the soft organs (viscera) of the body. It is divided by the thin diaphragm muscle into the cranial thoracic cavity, also known as the thorax or chest, and the caudal abdominal cavity, also known as the abdomen.

What portion of a serous membrane covers the outer surface of organs?

The visceral layer

What is the difference between the visceral and parietal layer of the pleura and peritoneum?

The visceral layer covers the organs and the parietal layer lines the whole cavity.

What is the xiphoid?

The xiphoid is the caudalmost sternebra.

How many nitrogenous bases are there?

There are five different nitrogenous bases: adenine (A), cytosine (C), guanine (G), uracil (U), and thymine (T). Adenine, cytosine, guanine, and thymine are found in DNA. Adenine, cytosine, guanine, and uracil are found in RNA. These five nitrogenous bases are further divided into two groups based on their molecular structure: purines and pyrimidines. Purines include adenine and guanine and have two rings in their molecular structure. Pyrimidines, which include thymine, cytosine, and uracil, are single-ringed molecules.

What is the basic cause of motion sickness?

There is a disagreement among the sensory receptors for the vestibular system, eyes, and proprioception, which can result in the unpleasant sensations of motion sickness, such as headache, nausea, and vomiting. The eyes look around the interior of the vehicle and see that nothing is apparently moving, but the equilibrium receptors and proprioceptors detect motion.

How are the hormones of the adrenal madela involved in the fight or flight response?

These effects of the fight-or-flight response are produced partly by direct sympathetic nerve stimulation of target tissues and partly by the epinephrine and norepinephrine released into the bloodstream by the adrenal medulla. The adrenal medullary hormones circulate around the body, helping to produce the whole-body fight-or-flight effect. After the threat has passed, it takes the body a while to come down from its excited state. This delay results from the epinephrine and norepinephrine circulating in the bloodstream. It takes some time for them to be metabolized and removed from circulation.

Why do non human animals often greet others by sniffing them?

They live in more of a smell-oriented world. They communicate and understand information by their sense of olfaction. For example, dogs obtain a huge amount of information from sniffing the air or an object where other animals have been.

When milking a cow by hand, why does it take a minute or two of teat stimulation before milk starts to flow freely?

This is how long it takes for the sensory stimulation to reach the brain and signal the hypothalamus to release oxytocin from the posterior pituitary and for the oxytocin to reach the mammary gland via blood circulation.

Name the bones of the thoracic pelvic limbs

Thoracic Scapula (shoulder blades) Humerus (upper arm) Ulna (forearm, forms elbow) Radius (forearm weight-bearing) Carpal bones (two rows of carpal forms carpus, our wrist or horse knee) Metacarpal (hand bones, only 1 in horses called cannon) Phalanges (toe) (horses have one digit composed of 3 phalanges: The proximal phalanx commonly called the long pastern bone, the middle phalanx commonly called the short pastern bone, and the distal phalanx, commonly known as the coffin bone. 2 proximal sesamoid bones at the fetlock joint, 1 distal in hoof called navicular bone) Pelvic Pelvis (ilium - most cranial, wing structure ischium-most caudal, sit on it pubis-medial) Femur (thigh) Patella (kneecap, largest sesamoid bone) Fabellae ( Two small sesamoid bones located in the calf muscle tendons just above and behind the femoral condyls of dogs and cats. Not present in cattle or horses) Tibia (main weight bearing, forms stifle joint with femur above and hock with tarsus below) Fibula (thin partial bone, muscle attachment) Tarsal bones (forms Tarsus, our ankle, or hock) Metatarsal (4 in dogs and cats, 1 cannon bone in horses)p Phalanges (toes)

11-4 What hormone plays an important role in helping an animal maintain its body temperature under cold environmental conditions? How does it produce its effects?

Thyroid hormone. It does this through its calorigenic effect. The production of thyroid hormone increases with exposure to cold temperatures. This response increases the body's metabolic rate, which generates more heat. It also causes nutrients to be burned at a faster rate; so to prevent significant loss of body weight, animals housed outdoors in cold temperatures need to be fed more calories than those kept in warmer temperatures.

How many types of fiber make up the cytoskeleton? Can you name them? How do they function differently?

Three different types of fibers compose the cytoskeleton, all of which are made of protein. The fibers are microtubules, intermediate fibers, and microfilaments. Microtubules form secure "cables" to which mitochondria, lysosomes, and secretory granules attach. Proteins that act as "motors" move the attached organelles along the microtubule from one location in the cell to another. Because microtubules act as the "railroad tracks" for organelle travel, they can be easily disassembled and then reassembled to form new paths or take a new direction. Intermediate fibers are woven, ropelike fibers that possess high tensile strength and are able to resist pulling forces on the cell by acting as internal guide wires. These fibers are the toughest and most permanent element of the cytoskeleton. Microfilaments play a key role in the cell's ability to change shape, break apart during cell division, and form outpouchings and involutions. In most cells, microfilaments are assembled where and when needed.

Give 3 examples of specialized connective tissue. How are they similar to connective tissue proper? How are they different?

Three types of dense connective tissue are cartilage, bone, and blood. Cartilage is similar to connective tissue proper in that it is composed of cells, fibers, and matrix. It is different in that it is more rigid than dense connective tissue. Bone is similar to connective tissue proper in that it is also composed of cells, fibers, and matrix; however, bone is much more dense. In fact, it is the hardest, most rigid type of connective tissue. Blood is similar in that it has a matrix, plasma, a fibrous component that is visible when blood clots, and cells. It is different in that it is almost always fluid but can clot when necessary.

What are 3 subtypes of dense connective tissue?

Three types of dense connective tissue are dense regular, dense irregular, and elastic.

List 3 types of muscle. How do they differ from one another?

Three types of muscle are skeletal, smooth, and cardiac. Skeletal muscle cells are striated, or striped, because histologically they have alternating bands of light and dark. Unlike cardiac and smooth muscle, skeletal muscle is usually controlled through conscious effort and therefore is called voluntary muscle. (In other words, the animal can control its movement through conscious thought.) Thus skeletal muscle is striated voluntary muscle. Smooth muscle is composed of small, spindle-shaped cells that lack striations or bands and therefore appear "smooth." Like skeletal muscle, smooth muscle may be stimulated to contract by the action of nerves, but unlike skeletal muscle, the contractions cannot be consciously controlled. Smooth muscle is therefore nonstriated involuntary muscle. Cardiac muscle exists only in the heart and possesses the remarkable ability to contract even when neural input has been altered. Specialized pacemaker cells within the heart muscle supply the signal for the heart to contract at regular intervals. This input is entirely involuntary and is responsible for initiating the pumping force that propels blood through blood vessels. Cardiac muscle is striated involuntary muscle.

What is threshold? What role does threshold play in the all-or-none principle?

Threshold is the number of sodium channels that must be opened in order for depolarization to occur. A stimulus must be strong enough for this threshold to be reached. According to the all-or-nothing theory, either the neuron depolarizes to its maximum strength or it does not depolarize at all (that is, the threshold is met or it isn't).

Describe the effects of thyroid hormone, calcitonin, and parathormone

Thyroid Hormone - Helps maintain body temperature (heats body) - affects metabolism in cells - promotes growth in young animals - helps maintain homeostasis of blood glucose levels - carbohydrate metabolism - encourages PROTEIN anabolism or catabolism - encourages catabolism of lipids Calcitonin - Prevents HYPERcalcemia (high blood calcium levels) by decreasing blood calcium level if it gets too high (encourages excess to be deposited in bones) Parathormone - Parathyroid hormone (PTH) - helps maintain blood calcium homeostasis with opposite effect of calcitonin. - Prevents HYPOcalcemia (low blood calcium levels) by increasing blood calcium levels - causes kidneys to retain calcium, intestines to absorb it, and withdraws calcium from the bones

Can you describe the events that occur in translation?

Translation is the process of making protein and occurs in the cytoplasm with the aid of ribosomes. Protein synthesis can occur either in cytosol, using free-floating ribosomes, or on rough endoplasmic reticulum (rRER), using fixed ribosomes. In the cytosol many free-floating ribosomes attach to a single strand of mRNA at the same time and begin "reading" the genetic sequence on the mRNA. The ribosomes that attach to the strand of mRNA form molecular "docking stations" that enable another molecule, transfer RNA (tRNA), to also bond to the mRNA strand. Each tRNA carries a specific amino acid and has a specific anticodon that correlates with the particular amino acid it carries. The "reading" process involves the bonding of a specific anticodon on the (tRNA to a complimentary codon on the mRNA. At the docking site tRNA molecules bond to the mRNA molecule, bringing the amino acids they carry into close approximation of one another. This allows the amino acids to bond directly to one another. Once the amino acid it carries is bonded to the adjacent amino acid, the tRNA molecule leaves the ribosome to pick up another amino acid. Over time a chain of amino acids, called a polypeptide chain, forms on the ribosome. When the chain has reached its required length, it disconnects from the ribosomal "docking station" and floats out into the cytosol (or if translation occurred on RER, the peptide is taken into the tubular cisternae of the RER for modification). Polypeptides are linked together to form proteins.

What are the 2 basic cell types that make up neural tissue?

Two basic types of neural tissue are neurons and supporting neuroglial cells.

Differentiate between T³ (triiodothyronine) and T⁴ (tetrauodothyronine, or thyroxine)

T³ - - Contains 3 iodine atoms per molecule - Most biologically active form of thyroid hormone - Active hormone T⁴ - - Contains 4 iodine atoms per molecule - Far more is produced - Functions as a circulating reservoir and is converted to T³ in peripheral tissues (liver, kidney, muscle) - Pro hormone

Describe the process of active transport.

Used for non lipid soluble, too large, or moving against a concentration gradients Active movement of molecules by specific carrier protein (with specific binding sites) Requires ATP Syports - all substances move in the same direction Antiport - some substances move in one direction, others in the opposite direction Ion binds to specific carrier protein, triggers release and use of ATP. Orientation of carrier protein changes, renders ion lipid soluble and allows carrier protein to move the ion through the cell membrane 3 Na+ pumped out, 2 K+ pumped in

How do the actions of gastrin on the stomach differ from those of secretin and cholecystokinin?

When released by stomach cells, gastrin stimulates gastric (stomach) glands to secrete hydrochloric acid and digestive enzymes, and it encourages muscular contractions of the stomach wall. Secretin and cholecystokinin are produced in the small intestine. Secretin stimulates the pancreas to secrete fluid rich in sodium bicarbonate into the duodenum to neutralize the acidic chyme from the stomach. Cholecystokinin stimulates the release of digestive enzymes from the pancreas into the duodenum. Both secretin and cholecystokinin also act on the stomach to inhibit gastric gland secretions and stomach motility. This slows the movement of chyme into the small intestine. They also stimulate the gallbladder of the liver to contract, sending bile down into the small intestine to aid the digestion and absorption of fats and fat-soluble vitamins.

How is the physical concept of inertia important to the functioning of the semicircular canals?

When the head moves in the plane of one of the semicircular canals, inertia causes the endolymph to lag behind the movement of the canal itself. The relative movement of the endolymph pulls on the cupula, which bends the hairs. This generates nerve impulses that give the brain information about the rotary motion of the head.

What happens to bones when the level of calcium in the blood falls to low? What happens when it rises too high?

When the level of calcium in the blood falls too low, osteoclast activity is increased to withdraw calcium from the bones and raise the blood calcium level. When the level of calcium in the blood rises too high, osteoblast activity is increased to deposit the excess calcium in the bones.

How is the crossed extensor reflex tied in with the withdraw reflex? Is the crossed extensor reflex an ipsilateral or contralateral reflex?

When the withdrawal reflex arc is stimulated, the afferent somatic sensory neuron also synapses with another set of interneurons, causing extensor muscles in the opposite leg to contract and thus support the weight of the body when the other leg flexes. Thus the withdrawal and crossed extensor reflexes are related. The crossed extensor reflex is a contralateral reflex.

In terms of its form and function, how is Brown fat different from white fat?

White adipose is found throughout the body, particularly in the deep layers of the skin. Initially, white adipocytes resemble fibroblasts, but as they fill with lipid, the organelles and nuclei are pushed to one side, and the cells become large spheres with eccentrically placed nuclei. As the cells swell, the cytosol is compressed into a thin, barely visible rim that surrounds the lipid droplet. Brown adipose fat is found in newborn animals and in animals that hibernate during the winter. It is a highly specialized form of adipose and plays an important part in temperature regulation because it is a site of heat production. In brown fat, as in white fat, the nucleus is eccentrically placed; however, the cytoplasm in brown fat is clearly visible, and lipid is stored in multiple small vesicles rather than in a single large droplet. In brown fat, the energy derived from the oxidation of lipids and the energy released from electron transport are dissipated as heat, not adenosine triphosphate (ATP). For this reason, brown fat contains an exceptionally high number of mitochondria (the site of electron transport), which become darkly stained in the cytoplasm. This dark coloration gives brown fat its name. Brown fat is also more vascular than white fat. Its rich vascular network helps distribute the heat produced to many areas of the body. In this way, neonatal animals and hibernating animals can generate enough body heat during vulnerable periods (after birth and during the winter) to survive. Histologically, brown fat looks glandular and therefore is sometimes called the hibernating gland.

Differentiate between white matter and Gray matter

White matter - nervous tissue containing many myelinated axons Gray matter - nervous tissue made up largely of neuron cell bodies

What is the difference between gray matter and white matter?

White matter refers to nervous tissue containing many myelinated axons. Conversely, nervous tissue that is made up largely of neuron cell bodies, which are not myelinated, appears darker and is called gray matter.

How would arthritis in the tiny joints of the ossicles affect hearing? Could this possibly affect the hearing of older animals?

Yes, arthritis could affect hearing in older animals. Arthritis could decrease the conduction of sound waves from the tympanic membrane to the oval window. The force of the vibrations would be decreased and the animal's hearing might be impaired.

Do FSH and LH play important roles in male animals? If so what are they?

Yes. In the male, FSH has an effect similar to one of its effects in the female. It stimulates spermatogenesis, the development of male reproductive cells (the spermatozoa) in the seminiferous tubules of the testes. In the male, LH stimulates cells in the testes called interstitial cells to develop and produce the male sex hormone testosterone. Therefore, LH is sometimes called interstitial cell-stimulating hormone (ICSH) in the male.

Differentiate between hyaline cartilage, elastic cartilage, and fibrocartilage

hyaline - most common type of cartilage found in the body. Composed of closely packed collagen fibers that makes it tough but more flexible than bone. Resembles blue-white, frosted, ground glass It is found as articular cartilage in the ends of long bones in joints, and connects the ribs to the sternum. Also forms supportive rings in the trachea and composes most of the embryonic skeleton. In growing animals it is found in the growth plates along bones where it supports continued bone development and the extension of the length of the bone. It is the most rigid type of cartilage and is enclosed within a perichondrium elastic - Similar to Hyaline cartilage but contains a plethora of elastic fibers which form dense branching bundles that appear black microscopically. These fibers give elastic cartilage tremendous flexibility so that it can withstand repeated bending. Found in the epiglottis of the larynx and in the external ears of animals fibrocartilage - Usually found merged with Hyaline cartilage and dense connective tissue. It contains thick bundles of collagen fibers, like Hyaline cartilage, but has fewer chondrocytes and lacks a perichondrium. It is particularly well designed to take compression and therefore is found in the spaces between the vertebrae of the spine, between bones in the pelvic girdle, and in the knee joint

Robert Hooke

looked at oak cork and was first to observe and name cells

Identify each of the following as being controlled by the autonomic or the somatic nervous system and as being either sensory or motor: Conscious movement of the forelimb Slowing of the heart rate in response to an increased blood pressure Constriction of blood vessels in the skin in response to cold temperatures Perception of pain from an injection of antibiotics Perception of the amount of acidity present in the duodenum

• Conscious movement of the forelimb: somatic, motor • Slowing of the heart rate in response to an increased blood pressure: autonomic; sensory for sensing the increased blood pressure and motor for slowing the heart rate • Constriction of blood vessels in the skin in response to cold temperatures: autonomic; sensory for sensing the cold temperatures and motor for constricting the vessels • Perception of pain from an injection of antibiotics: somatic, sensory • Perception of the amount of acidity present in the duodenum: autonomic, sensory