Bio Exam 3
Know the steps of fertilization in Sea Urchins
1. Sperm cell contacts jelly coating & acrosome releases enzymes. 2. Acrosomal enzymes digest a hole in jelly coating allowing penetration of sperm cell. 3. Species-specific proteins on sperm cell bind to species-specific receptor proteins on the egg. 4. Sperm & egg cell plasma membranes fuse, allowing sperm nucleus to enter egg cell (time zero). 5. Egg cell plasma membrane becomes impenetrable to other sperm cells (< 2 sec.). 6. Vitelline layer hardens & separates from plasma membrane, becoming impenetrable to sperm (20 sec); meiosis II finishes; nuclei fuse (20 min); 1st cell division (90 min).
Know the steps of the sodium/potassium pump. S10
A potassium atom is about 33% bigger in diameter than a Na atom.
What are the 3 types of nitrogenous wastes? Which one is for humans, why? S17 -19
Ammonia: Most aquatic animals, including most bony fishes. (Very soluble, but relatively toxic. Can not accumulate to high concentrations. Requires a lot of water for excretion. Good for most fish & aquatic animals. Excreted via gills & skin surfaces.) Urea: (HUMANS) Mammals, most amphibians, sharks, some boney fishes. (Less toxic, but still relatively soluble. Can be accumulated to higher concentrations. Allows for conservation of body water, but . . . Must be excreted with water; requires drinking. Occurs in mammals, sharks, adult amphibians. Toxic (denatures proteins) at high concentrations.) Uric Acid: Birds, many reptiles, insects & land snails. (Non-toxic substance, with poor solubility in water. Can be made highly concentrated. Allows maximum water conservation. Requires more complex metabolism & energy. Excreted as semi-solid paste by birds, reptiles & insects. Allows habitation with minimal water.)
Know the types of reproduction, their characteristics, and the advantages and disadvantages of each. S2-9
Asexual Reproduction Types of Asexual Reproduction Include . . -Fission -Cell Division (binary fission) -Budding -Fragmentation & Regeneration -Parthenogenesis Advantages of Asexual Reproduction -Normally faster than sexual reproduction -Beneficial in stable, unchanging habitats -Beneficial for sparse populations or where individuals do not move The advantage of asexual reproduction is that a partner is not required, it is not energy intensive, and the population can be maintained quickly. Asexual reproduction is a result of mitotic events. Sexual Reproduction In Animals . . . -Male gametes (i.e. sperm) -Female gametes (i.e. eggs) advantages the animal kingdom gives us many varieties on this them.
What are the structures and functions of the blood brain barrier, (BBB)? S30
Blood-Brain Barrier - the selectively permeable barrier between the capillaries of the brain & the surrounding cellular matrix of the brain. Tight junctions between endothelial cells. Allows passage of nutrients & oxygen, but not metabolic wastes from other parts of the body. Helps to maintain a stable chemical environment for the brain. Remember - Astrocytes are "transfer cells" that transfer glucose & other nutrients from the blood vessels into nerve cells. •From before . . . Astrocytes transfer nourishment from capillaries to neurons & other glial cells of nervous tissues. •Approx. 20 - 25 % of the body's blood passes through the brain. •Blood brain barrier protects against most blood-borne pathogen, does not allow passage of white blood cells, antibodies. BBB permeability becomes more leaky with inflammation of brain. •Cerebrospinal fluid fills ventricles & surrounds brain for neutral buoyancy & protection against impact with skull. CSF flows throughout the inner ventricular system in the brain and is absorbed back into the bloodstream, rinsing the metabolic waste from the central nervous system through the blood-brain barrier. •Hydrocephalus (aka "water on the brain"), is a medical condition in which there is an abnormal accumulation of cerebrospinal fluid (CSF) in the ventricles of the brain. This may cause increased intracranial pressure inside the skull •Meningitis - inflammation of the membranes (meninges) surrounding the brain and spinal cord; most are caused by viral infections & some bacterial infections; symptoms include headache, fever, stiff neck & swelling of affected areas.
What is important about language as a form of communication? S37
Body Language as a Form of Communication? Types of Communication: Spoken words = 7% Tone of voice = 38% Body language = 55% Gesture, posture, movement, facial expression. Processed by right hemisphere
What do bone cells do throughout life? Name and define the different cells.
Bone cells repair & reshape bones throughout life. Osteogenic cells - stem cells that give rise to all other bone cells. Osteoblasts - bone-forming cells; remove calcium from blood & deposit Ca2+ salts into forming bone. Osteocytes - mature bone cells trapped or located in lacunae of bone that maintain bone tissue; thought to be the "mechanosensor cells" that control the activities of osteoblasts & osteoclasts. Osteoclasts - bone-absorbing cells; breakdown bone & return calcium to blood.
how is childbirth induced
Childbirth Is Induced by Hormones & Other Chemical Signals. -Highest levels of estrogen -Estrogen stimulates -Fetal cells & mother's pituitary gland Oxytocin stimulates . . . -Prostaglandins stimulate -Amnion ruptures
Know the different types of joints and what they do and an example of each. S15-16
Fibrous Joints - tight immovable joints, where separate bones are held together by connective fibers (e.g. bones of skull and tooth & socket joints). Cartilagenous Joints - slightly movable joints between bones that are joined together by strips or disks of cartilage (e.g. in ribs, vertebrae & hip bones). Synovial Joints - freely movable joints that are enclosed in a fibrous capsule; bones are separated by a fluid-filled cavity and stabilized (held together) by ligaments. Ball-and-socket joints - enable rotation in the arms and legs. Hinge joints - in the elbows and knees permit movement in a single plane. Pivot joints - enable the rotation of the forearm at the elbow. Above joints are shoulder, and elbow (2nd two). Another pivot joint occurs between the first & second cervical vertebrae and allows rotation of the head from left to right. Another "ball & socket" joint is the hip joint.
What are the four ways antibodies mark antigens for elimination? S26
Four Ways that Antibodies Mark Antigens for Elimination 1. Neutralization (blocks viral binding sites; coats bacteria) 2. Agglutination (of microbes) 3. Precipitation (of dissolved antigens) 4. Activation of the complement system Antigen with bound antibodies are ineffective. Bound antibodies serve as signal flags for phagocytosis by macro-phages. A good example of "precipitation" of dissolved antigens would be with bee venom or snake venom. The active ingredients are soluble molecules (proteins) that would eventually be inactivated via precipitation. For activation of the complement system, a complex of complement proteins binds to free end/stalk of antibody. This binding triggers the activation & release of complement protein (that is now very close to the foreign cell). These then insert into the foreign cell membrane to form a pore or channel (aka as a membrane attack complex previously) through which water can freely enter causing lysis. Thus, some complement proteins are involved in adaptive immunity (here) or innate immunity (earlier).
Understand cleavage, gastrulation
Gastrulation Produces a Three-Layered Embryo
What are some examples of diuretics? What causes kidney stones? S29, 31
Diuretic - a drug (or chemical) that promotes the formation & elimination of urine from the body; they variously function by counteracting the effects of ADH. Often prescribed to treat hypertension (i.e. high blood pressure) & congestive heart failure. Common diuretics include beverages containing caffeine & alcohol; some foods/herbs (e.g. hawthorn, dandelion & celery) Hawthorns have procyanidins as their diuretic(s); dandelion has flavonoids. Caffeine is an adenine analog. Kidney Stones - crystallized precipitates of calcium oxalate, uric acid or cystine that variously form in the ducts of the kidney. Impair/block normal kidney function.
In innate immunity, what comprises the 1st and 2nd line of defenses and their functions? S4-6
Innate immunity includes exoskeleton, low internal pH, lysozyme, phagocytes, recognition proteins 1st line of defense- (barrier to entry) Skin, Mucous membranes 2nd line of defense- (innate immune cells) netrophils macrophages natural killer cells
Know the main components of the urinary system, and it major roles in homeostasis. AND the Two main functions.
Main Components: 1.Kidneys - produce urine. 2.Renal Artery & Vein - transport blood to & from the kidneys. 3.Ureter - conducts urine from the kidney to urinary bladder. 4.Urinary Bladder - stores urine until voided from the body. 5.Urethra - conducts urine from the urinary bladder to the exterior of the body. Two Main Functions: 1.Form & excrete urine. 2.Regulate water & solute content in body fluids.
Know the two main types of immunity and describe in detail the components and their functions of each.
Two Main Types of Immunity 1.Innate Immunity Aka non-specific, genetic, or natural immunity. Involves a set of defenses that are immediately active, and independent of previous encounters with a given pathogen or substance. Are the same, whether or not the pathogen has been previously encountered. Found in both vertebrates & invertebrates. 2.Adaptive Immunity Aka acquired immunity. Involves a set of defenses developed for, and activated by specific pathogens or substances. Immune system "remembers" (or specifically recognizes) a previously encountered pathogen. Found only in the Vertebrates.
Know skeletal/muscle interactions in movement, 3 classes.
The Skeleton & Muscles Interact in Movement. A muscle can only move bone by contraction (not by expansion). Muscles must work in opposing pairs to effect bi-directional motion. Muscles & bones function like levers. Triceps ® 1st class. Calf muscle ® 2nd class. Biceps ® 3rd class. Attachment = orange square Pivot point = red triangle Arrow = force direction and placement of force
what are the three stages of childbirth?
The Three Stages of Labor 1. Dilation of the Cervix. 2. Expulsion (delivery). 3. Delivery of the Placenta.
What are the 3 main functions of the nervous system. S4
Three Main Functions: 1.Sensory Input - conduct signals from receptors to CNS. 2.Integration - analysis & interpretation of sensory signals, & formation of appropriate responses. 3.Motor Output - conduct signals from CNS to effectors that execute a response. Backpacking Example: Sensory input: gradually smell smoke, start to hear crackling, look up & see fire. Integration: There's a forest fire, it's pretty big & dangerous, better get out of the area. Motor output: Start walking, running away.
What are the 3 main types of neurons and what are the 4 steps of the reflex arch? S5-6
Three Main Types of Neurons 1.Sensory neurons - receive stimuli, convey signals from sensory receptors to the CNS. 2.Interneurons - are located entirely in the CNS, integrate information & send it to motor neurons. 3.Motor neurons - convey signals to effector cells. 1.Look at the Knee-Jerk Reflex Arc 1.Sensory receptor detects stretch stimulus. 2.Sensory neuron sends impulse to the CNS (spinal cord). 3.Impulse is transferred from the CNS to motor neurons . . 4.And interneurons.
Describe the complement system, Inflammatory response and the steps. S7, S8-9
complement proteins... 1. enhance inflammation- bind to mast cells & trigger more histamine release 2. help target cells for destruction- bind to cells coated with antibodies as extra signal to phagocytes 3. form membrane attack complexes inflammation mobilizes the innate immune response from before... inflammation fever
Which organisms have or do not have these types of immunity? S2-3
•All Animals Have Innate Immunity Invertebrate Innate Immunity Includes . . . Exoskeleton - a hard impermeable chitinous "shell" that prevents the entry of foreign microbes. Low internal pH - that inhibits the growth of microbes. Lysozyme - an enzyme that degrades bacterial cell walls, causing them to lyse and die. Phagocytes - circulating immune cells that engulf and digest foreign substances. Recognition proteins - bind to microbes & trigger the release of antimicrobial peptides. •The pH of insect hemolymph typically ranges from 6.4 - 6.8. •Lysozyme is found in several types of secretions, such as tears, saliva, human milk, and mucus. It is also present in macrophages and neutrophils. •Insects have a peptidoglycan recognition protein (PGRP), and a gram-negative binding protein (GNBP) that help to recognize bacteria. Other recognition proteins seem to be specific for fungi. Both trigger the release of antimicrobial peptides. •Drosophila (and mosquitos) is/are models for studying innate immunity in insects. General Characteristics of Adaptive Immunity Only found in the Vertebrates.
What is the difference between an unmylenated and myelinated neurons and where are each of them found? S19
•Impulse Transmission in Unmyelinated vs. Myelinated Neurons •Myelinated neurons occur mainly in the peripheral nervous system where impulses must normally travel further. •Unmyelinated neurons occur mainly in the CNS as interneurons, where impulses travel much shorter distances between sensory & motor neurons. •Impulse transmission is about 20-100 x's faster in myelinated neurons.
the differences between freshwater and marine fishes in osmoregulation?
freshwater fishes: Gain of water andsome ions in food Uptake of salt ions by gills Osmotic water gain through gills and other parts of body surface Excretion of salt ions and large amounts of water In dilute urine from kidneys marine fishes: Gain of water andsalt ions from food and drinking sea water Excretion of salt Ions from gills Osmotic water loss through gills and other Parts of body surface Excretion of salt ions and small amounts of water in concentratedurine from kidneys
What is Thermoregulation? What are the two main types?
thermoregulation: a form of homeostasis by which animals maintain an internal temperature within a tolerable range. Endotherms - "warm-blooded" animals that warm themselves via heat derived from their own metabolism (e.g. mammals, birds & most vertebrates). Ectotherms - "cold-blooded" animals that warm themselves by absorbing heat from their surroundings (e.g. fish, amphibians, lizards, snakes, most invertebrates).
Heat is gained or lost in 4 ways.
1.Conduction — the transfer of heat by direct contact. 2.Convection — the transfer of heat by movement of air or liquid past a surface. 3.Radiation — the absorption or emission of electromagnetic waves. 4.Evaporation — the loss of heat from the surface of a liquid that is losing some of its molecules as a gas.
Four Key Processes of the Urinary System
1.Filtration - at the glomerular (Bowman's) capsule. Water & small molecules pass. Proteins & cells are retained. 2.Reabsorption - by capillaries surrounding proximal & distal convoluted tubules. Reclaims valuable solute (glucose, salts, amino acids) & returns them to blood stream. 3.Secretion - by capillaries surrounding proximal & distal convoluted tubules. Includes harmful compounds not filtered into the glomerulus (e.g. residual ammonia, uric acid). Creatinine, histamine, penicillin, H+ & K+ ions. 4.Excretion - from kidneys via ureter, bladder & urethra. Creatinine is a breakdown product of creatine phosphate in muscle.
How are helper T cells, cytotoxic T cells, and B cells activated? S28
1.Macrophage ingests & degrades foreign cells or material, and breaks it into antigenic fragments. 2.Self proteins bind to foreign non-self molecules/antigens. 3.Self/non-self complexes are displayed at cell surface. 4.Virgin helper T cells bind to self/non-self complexes (= recruitment /activation). 5.Signal molecules stimulate division of activated Helper T cells to form memory T cells and effector T cells. 6.Activated Helper T cells secrete Interleukin-2 which . . . AND: Activated HT cells bind to "presented antigens" on B cells, which activates them to promote division & formation of plasma cells that release antibodies. Interluekin-1 tends to stimulate the inflammatory response, while IL-2 tends to stimulate proliferation of HT cells. 7. Activates B cells (& the humoral response), and Cytotoxic T Cells (& the cell-mediated response). Apparently, many of the newly proliferated HT cells become cytotoxic T cells, and some of these become memory cytotoxic T cells. Antigen presentation stimulates T cells to become either "cytotoxic" CD8+ cells or "helper" CD4+ cells.
Five times of thermoregulation Involves Adaptations that Balance Heat Gain and Loss.
1.Metabolic Heat Production - increased rates of metabolism give off more heat (e.g. vigorous exercise & shivering). 2.Insulation - such as hair, feathers, fat. 3.Circulatory System Adaptations: Counter current heat exchange. Changes in blood flow to/from skin. 4.Evaporative Cooling: Sweating, panting, spreading saliva. Transpiration in plants 5.Behavioral Responses: Movement to warm vs. cool environments. Bathing, seasonal migrations.
Where do B & T cells form and where they mature? Describe the development of B cells versus T cells. S19-20.
A Closer Look at The Development of B Cells vs. T Cells Both originate in bone marrow from stem cells. B cells mature in marrow. T cells mature in thymus. Genes for antigen receptors are "scrambled". Each cell can produce only one type of antigen receptor. Millions of "receptor unique" cells take residence in the lymphatic system. Each cell can bind only one type of antigen. Scrambling of genes during maturation of lymphocytes is refered to as "V(D)J recombination"; this is a form of somatic cell recombination during cell development. Mature B Cells & T Cells are transported to lymphatic organs (e.g. nodes, spleen, tonsils) & "wait until recruited". Recruitment = first antigen recognition - cell division is activated; many more cells are produced. Humoral Response - B cells release antibodies that tag (mark) antigens in body fluids for destruction. Cell-mediated Response - T cells actively engage & destroy infected cells of the body.
Know the mechanism of filament sliding. slides 20 through 27.
A Muscle Contracts When Thin Filaments Slide Along Thick Filaments The Sliding Filament Model Thin filaments of actin are pulled into linear spaces between thick filaments by myosin motor proteins that make up the thick filaments. Sequence of Steps in the Mechanism of Sliding Filaments 1.ATP binds to myosin head, resulting in the low energy (detached) configuration. 2.Myosin hydrolyzes ATP to ADP & Pi; both remain bound to myosin; energy released causes the myosin head to extend to the actin filament. 3.Myosin head latches onto its actin binding site forming a cross bridge between the two filaments. 4.ADP & Pi are released, and the myosin head reverts back to its low-energy configuration (i.e. the "power stroke"), causing the actin filament to move toward the center of the sarcomere. 5.The cross bridge remains attached until another ATP binds to the myosin head, thereby repeating the above process. 6.The sequence: detach, extend, attach, pull, detach repeats many times; the combined action of hundreds of heads results in the contraction of the entire muscle
How do helper T cells stimulate the humoral and cell mediated immune responses? S27
Background on Helper T Cells . . . T Cell Lymphocytes that trigger humoral & cell-mediated immune response. They must first be "activated" (or "recruited) into action - i.e. "naïve" or "virgin" cells must encounter their first antigen. Involves complex self/antigen receptors. First exposure to antigen only occurs via macrophage "antigen presenting cells". Antigen-Presenting cells include: Macrophages & B cells. Activated Helper T Cells then activate . . . B cell lymphocytes (Humoral Response). Cytotoxic T Cells (Cell-mediated response). Note: All (nucleated) cells of the body can present antigens (especially) if/when they become infected by a bacterium or virus, however, antigen presenting macrophage cells are very specialized and efficient at this function. Thus they are often referred to as "professional" APC's. Other cells of the body (besides macrophages, dendritic cells,) are referred to as "Non-professional" APC's. Self proteins are aka "Major Histocompatibility Complex" proteins, which are the same as those that determine compatibility for organ transplants.
What is clonal selection? Describe it in detail. S22-23
Clonal Selection Mobilizes Defenses Against Specific Antigens Clonal Selection (aka clonal recruitment): The process whereby genetically unique (naïve or virgin) lymphocytes react with (recognize) their specific antigen for the very first time. Stimulates their mitotic proliferation. Note: Clonal selection of T cells occurs at essentially the same time (but by different mechanism - see later). These B Cells must be activated by helper T cells (see later). Leads to the production of Effector B Cells (aka Plasma Cells) and Memory Cells. Effector/Plasma cells produce & secrete massive amounts of antibodies (2000/sec). Memory Cells migrate to lymph nodes to respond to subsequent invasions. Last for decades. Activated by Helper T cells. Macrophages destroy antigens bound to antibodies. Also involved in "antigen presentation". Memory Cells •Help activate immune system upon subsequent infections. •Last for decades. Effector Cells •Highly effective at combating an existing infecton. •Last 4 - 5 days before dying.
Why are bones complex living organs?
Costas = Latin for ribs (remember the intercostal muscles). The spine has 33 vertebrae The human foot has 26 bones; human hand has 27 bones; 12 pairs of ribs; and 22 skull bones. Carpals = wrist; metacarpals = bones of the palm; phalanges = bones of the fingers (and toes). Pectoral Girdles: collarbones and shoulder blades (i.e. clavicle & scapula). Pelvic Girdle: fused hipbones. Sacrum - triangular bone at the base of the spinal cord. Coccyx - the final segment of the human vertebral column (more commonly called the "tailbone"). •Periosteum is a membrane composed of dense, irregular, fibrous connective tissue that lines the outer surface of all bones except at the joints of long bones. It protects bones from harm and serves as a site for muscle attachment. The periosteum is the primary source of precursor cells which develop into chondroblasts( cartilage cells) and osteoblasts ( bone cells) that are essential to the healing of broken bones. •The central canal of the osteon is sometimes referred to as a "Haversion Canal" •Red bone marrow - all bone marrow is red at birth, but red marrow gradually converts to yellow marrow as we become adults. After adulthood, only flat bones and ends of long bones (i.e. "spongy bone tissue") contains red marrow. •Yellow bone marrow is yellow because it is enriched in & stores fat that can be used as a last resort as a source of food/energy during extreme starvation. More importantly, it can convert back to red bone marrow in 1-2 days in cases of severe blood loss. This occurs to help quickly replenish the supply of RBC's that is urgently needed. •Cartilage at the ends of bones - cushions joints; reduces friction of movements. •Fibrous connective tissue (periosteum) covering most of the outer surface of bone forms new bone in the event of a fracture.
How do cytotoxic T cells destroy infected body cells, (know the steps)? S29
How a Cytotoxic T Cell Kills an Infected Cell 1.A cytotoxic T cell binds to an infected cell. 2. Perforins form holes in the infected cell's membrane, and enzymes trigger cell death. 3. The infected Cell dies. 4. Cytotoxic T cell detaches and can destroy other cells infected by the same pathogen. Most cells of the body (when infected by a foreign pathogen / virus) will "present" antigen fragments as "self/non-self" complexes. Cytotoxic T cells are the only T cells that kill infected body cells; they also play a role in protecting against some cancers. They are not the same as "natural killer cells". Caspases are CTC enzymes (proteases) that promote apoptosis. Natural Killer Cells are different from Cytotoxic T Cells in the following ways: •NK cells are part of the innate immune response (not the adaptive response). •NK cells look for infected cells that have lost "self markers", when they find them, they kill them in a manner similar to cytotoxic t cells, except that . . . •They are not specific for any given cell surface antigens. •They do not have "memory" •Their numbers do not increase upon exposure to antigen.
how is it determined how much of the brain controls parts of the body? See slide 36.
How are the various regions of the brain mapped out ? Traumatic brain injuries accompanied by altered neurobiology (symptomology), followed by post-mortem autopsies. Neurostimulation during brain surgery - Wilder Penfield - Canadian neurosurgeon - used "trial & error" electrical stimulation of various parts of the brain during surgery. Phineas Gage (1848) had a railroad spike pierce his face/skull that damaged his frontal lobe, thus altering his ability to process emotions & make rational decisions. Inset = a 1994 computer reconstruction. •During the 1940's and 1950's, Canadian neurosurgeon Wilder Penfield performed extensive brain surgeries on patients with local anaesthetic. During the operations, he stimulated specific regions of the patients' brains with an electrode and simply asked them what they felt. All kinds of sensations, images, and even memories were elicited by the electrode, and the somatosensory areas of the brain that were responsible could be mapped (info. From McGill University). •Parts of the human body are proportionally distorted to represent which parts receive the most precise control with the greatest number of both sensory & motor neurons.
types of osmoregulation in land animals with examples
Land animals lose water by . . . Evaporation & waste disposal. Gain water by drinking and eating. Land animals conserve water by . . . Reproductive & behavioral adaptations. Waterproof skin & efficient kidneys. •Laying eggs & fertilization in watery habitats. •Development of the "amniotic egg" (w/a waterproof coating or shell). Kangaroo rats live in desert environments; •Produce most hypertonic urine of the animals; extremely dry fecal pellets; produce most of their water via cellular respiration. •they also exhibit nocturnal behavior - its much cooler at night for foraging; during the day the stay in deep cool burrows.
What is metabolic water? S16
Metabolic Water? MW of glucose = 180; MW of 6 H2O = 108. Thus, for every gram of CHO (i.e. 0.00556 moles) consumed, 0.6g (0.0333 moles) of water is produced. Water released into the tissues during the metabolism of foodstuffs. For example, during cellular respiration water is a by-product of the oxidation of carbohydrate and free fatty acids.
How do motor neurons stimulate muscle contraction? Why is acetylcholine important in this function? What is the function of acetylcholine and how do the myosin heads cause actin filaments to "slide" relative to myosin filaments? S28-30
Motor Neurons: Carry nerve impulses (action potentials) from the CNS to muscles. Axons of each motor unit branches out to synapse with many muscle fibers (cells). Synaptic terminals release acetylcholine into the synaptic cleft. Acetylcholine initiates a muscle contraction Motor Unit - a single axon that branches to (or synapses with) approximately 2000 individual muscle fibers (cells). Acetylcholine triggers an action potential in the muscle cell plasma membrane. The action potential travels in all directions along the surface of the muscle cell, and deep into the cell via T tubules. Depolarization of T tubules triggers the release of Ca2+ ions from the endoplasmic reticulum (aka sarcoplasmic reticulum). T Tubules: The "T" of T tubules stands for "transverse". T tubules are transverse infoldings of the plasma membrane.
Describe the different types of movement versus the different types of locomotion. What are their functions? What do they provide? S3-4
Movement vs. Locomotion: Movement: A distinguishing characteristic of animals. Involves changing position of body parts relative to one another. All require energy, & rely on the movement of cellular strands of protein against one another. Locomotion: Active travel from place to place. Requires movement of body parts. Requires additional energy to overcome gravity & friction. Animals that "move" but don't locomote: Sponges, anemones, tubeworms, muscles. (sponges can closes their oscula & pores via contractile proteins in specialized cells). Cellular strands of protein include actin filaments for cytoplasmic streaming; microtubules for movement of chromosomes, motor proteins that effect physical motion. Types of Locomotion Swimming - Supported by water; nominal effects of gravity; slowed by friction. Walking -Less overall friction between air and the animal; must resist gravity; requires good balance.
Nerve function depends on??? S9
Nerve Function Depends on Charge Differences Across Neuron Membranes. Outside = positive. Inside = negative. Resting potential = -70 mv. Created & maintained by the Na/K pump. [Na+] high outside neuron. [K+] high inside neuron. Collapsed by Na+ & K+ ion channels.
Know the structure and function of the nervous system components. S3
Nervous System - an animal organ system comprised of a network of specialized interacting cells (neurons) that functions in the detection, processing and response to internal and external stimuli. Functionally divided into . . . The Central Nervous System - comprised of the brain & spinal cord. Peripheral Nervous System - comprised of nerves outside the CNS that carry signals into & out of the CNS. Consists of . . . Nerves - bundles of neurons wrapped in connective tissue. Ganglia - clusters of neuron cell bodies.
What are the processes that give form to the developing animal? Know each and why each is important. What is important about the homeotic genes? S34-38
Organs develop from the three embryonic layers: organogenesis Multiple Processes Give Form to the Developing Animal. Processes include . . . -Embryonic Induction -Cell Migration -Apoptosis Homeotic Gene: Genes that regulate Base sequences & physical positions They code for transcription factors
What is osmoregulation? Know the 2 types of osmoregulation strategies
Osmoregulation - the homeostatic control & balance in the uptake and loss of water and solutes such as salt and other ions. Two Main Osmoregulation Strategies: - Osmoconformers - animals with body fluids having a solute concentration equal to that of seawater, thus without major challenges in water balance. •Includes many marine invertebrates (e.g. squids, star fish, anemones etc.). - Osmoregulators -animals with body fluids having solute concentrations that greatly differ from their environment. •Includes land animals, freshwater fish, marine vertebrates.
What are the 3 osmotic systems or scenarios?
Osmosis - the spontaneous net movement of a solvent (water) through a semi-permeable membrane from a region of lower solute concentration to a region of high solute concentration. Isotonic - [solute]out = [solute]in No net gain or loss of water Hypertonic - (freshwater fish)[solute]out > [solute]in (Water diffuses out cell) Hypotonic - (saltwater fish) [solute]out < [solute]in (Water diffuses into cell)
What are the different parts of the human skeleton, functions, names of bones.
Rigid for support of entire body. Protection of vital internal organs: Skull - protects brain. Rib cage - protects heart & lungs. Vertebrae - protects spinal cord. Storage - of Ca2+ & PO43- salts & fat. Production of blood cells (by red bone marrow). Provides a site for muscle attachment. Combined with flexible joints - promotes body movement & locomotion via a series of "levers". Third Class Lever - the most common in the human body.
know spermatogenesis in the human male.
Spermatogenesis in the Human Male Occurs in the seminiferous tubules of the testes. Diploid spermatgonial stem cells occur near the walls of tubules. Spermatogenesis - production of sperm Spermatogenesis takes place in the testes in the seminiferous tubules. Stem cells go first go through mitosis to produce a spermatogonium cell. This cell then undergoes meiosis. The completion of meiosis produces four spermatocytes. This process is supported by Sertoli cells. Lydig cells within the testes are responsible for producing testosterone which is necessary for sperm maturation. Early spermatids are pushed toward the epididymis where they mature into sperm cells. Each mature sperm has a long tail of flagella, a ring of mitochondria, a capsule containing DNA, and an acrosome of digestive enzymes on the head.
What are the 4 steps of allergies? S37-38
Stage 1 - Sensitization - i.e. the very first exposure to an allergen - i.e. the antigen that elicits the allergen. Stage 2 - Over Reaction - i.e. over-stimulation of the inflammatory response during a later exposure to the same antigen. Can be life-threatening or fatal. The two stages of allergic reactions parallel the primary & secondary stages of immunizations (except that the second stage comes much sooner than the booster). Ragweed flower & pollen; peanuts as allergens; penicillin (g). Trees (especially oaks) produce copious amounts of pollens; then weeds & grasses (especially ragweed); Stage 1: Sensitization 1.Allergen enters the bloodstream. 2.Virgin B Cells are recruited to produce antibodies. 3.B Cells develop into plasma cells that release antibodies. 4.Antibodies attach to mast cells Stage 2: Over reaction 5.Allergen enters the body a second time & binds to antibodies on mast cells. 6.Mast cells release histamine, which triggers allergy symptoms, including the inflammatory response. Inflammation of nasal membranes results in typical allergy symptoms (runny nose, tearing eyes, sneezing).
What does the structure of an antibody match its function? S25
Structure & Function of Antibodies Y-shaped protein receptor molecules (aka Immunoglobins) produced by B cell lymphocytes. Comprised of four polypeptide chains: Two heavy + two light chains, Each with variable & constant regions. Each recognizes or binds only one specific antigen. All function to "neutralize" antigens and/or mark them for destruction via phagocytes Phagocytes recognize & bind/attach to base of "Y". Humoral - refers to non-cellular substances that occur in the fluids (especially blood) of the body. Antibodies are the most common "non-cellular" substance. Disulfide bonds (between cysteine residues) hold antibody subunits together.
How is an action potential propagated along the axon? S18
The Action Potential Propagates Itself Along the Axon. 1.Once an action potential is initiated, Na+ channels open, resulting in the influx of Na+ ions; this triggers a similar influx of Na+ in adjacent regions of the plasma membrane. 2.Once the influx of Na+ is completed, Na+ channels close & K+ channels open, resulting in an efflux of K+ ions. 3.Migrating action potential continues along the entire length of the axon; Na/K pump re-establishes correct membrane resting potential. 4.Impulse travels @ 50-60 m/sec. (15-20 msec to travel 1 meter) Speed of impulse transmission along a neuron is 10's of meters/sec (e.g. 50 - 60 m/sec; 100 - 200 mph; depending on the size of the neuron). Or, it would take about 15 - 20 msec for an impulse to travel 1 meter. Refractory period for neuron function is approx. 1 - 2 msec.
Adaptive immunity, how can it be acquired? S10-12
The Adaptive Immune Response Counters Specific Invaders. General Characteristics of Adaptive Immunity Only found in the Vertebrates. A second line of defense - when innate (non-specific) immune response fails to ward off a pathogen. Slower than innate defenses - i.e. normally takes 5 - 7 days to mount a response). Highly specific - involves the recognition of foreign cells, particles & molecules (i.e. "antigens") as "non-self" by the immune system. Recognition is mediated by antibodies. Can "remember" antigens or pathogens that have been encountered before. Involves B Cell & T Cell Lymphocytes. Often referred to as "acquired immunity".
What happens in each of the three trimesters of pregnancy
The First Trimester -The embryo forms, -Extra-embryonic membranes. -All major organ systems -Called a fetus after 8-9 weeks The Second Trimester 13-27 weeks The Third Trimester (28 weeks - birth) -Also a time of rapid growth where . . . -The circulatory and respiratory systems -Muscles and skeleton -Average length -Average weight -First (but low)chance of premature survival
Know oogenesis in the human female.
The Human Female Reproductive Cycle oogenesis: Oogenesis Produces Only One Mature Egg Eggs begin production before birth and meiosis does not complete until the sperm nucleus penetrates. A single germ cell goes through a mitotic division to establish a primary oocyte that is arrested in prophase of Meiosis I. At puberty, a single primary oocyte begins to develop each month inside a follicle of supporting cells. Meiosis will begin and a secondary oocyte (and a polar body) will be formed and arrested at metaphase of meiosis II. This secondary oocyte is released at ovulation. If, and only if, a sperm enters the oocyte will it progress through meiosis II.
Know the flow and what happens in the kidney, from Bowman's capsule, proximal tubules, loop of Henle, distal tubules, and the collecting duct, renal pelvis, ureter, bladder, urethra.... What molecules are reabsorbed, and which one are released. S21-27
The Kidney is a Water-conserving organ 1.Most nutrients in the filtrate (glucose, amino acids, NaCl) are reabsorbed by capillaries in the proximal tubules. Aprrox. 65% of the filtrate water follows by osmosis. 2.NaCl is actively transported out of the ascending loop & is reabsorbed by the capillary bed; water follows by osmosis & is facilitated by aquaporins in the descending limb. 3.Water reabsorption stops in the ascending limb (which is not permeable to water). 4.More NaCl is reabsorbed at distal tubules followed by water. 5.More NaCl (& more water) is reabsorbed by collecting duct; some urea leaks out of the duct & is also reabsorbed. Approximately 99% of the filtrate water is reabsorbed. Creatinine is a breakdown product of creatine
What are the parasympathetic and sypathetic divisions of the nervous system? What does each one do? What do they control? S32
The parasympathetic and sympathetic divisions of the autonomic nervous system control the same organs, but in opposition to each other. Fixed constricted/pinpoint pupils can point to damage of the Pons region of the brain, or other traumatic brain injuring including stroke or opiate obuse/overdose (opiates like morphine stimulate the Parasympathetic system). Fixed dilated pupils can be an indication of head trauma/brain damage, or severe injury.
Describe the different types of skeletons. S5
Three Main Types of Skeletal Systems: 1.Hydrostatic skeletons - A skeleton made up of fluid held under pressure in a closed body compartment; the shape of the compartments controls the animal's form. Found in worms and Cnidarians. (e.g. Hydra, jelly fish), the worms (e.g. Planarians, nematodes, earthworms). 2.Exoskeletons - rigid "non-living" external skeletons (or shells) that are found in arthropods & Molluscs. They consist of . . . Chitin and protein in Arthropods. Must be shed to permit growth. Calcium carbonate in Molluscs. Molting Cicada & molting crab Endoskeletons - hard or leathery supporting elements situated among the soft tissues of an animal. They are made of . . . Cartilage or cartilage and bone (vertebrates). Spicules (sponges). Spicules are variously made out of calcium carbonate, silica, while others are made of spongin. Starfish endoskeletal plastes are made of calcium carbonate (for some support), but they also utilize a hydroskeleton for locomotion, the endoskeleton is mostly for support. Hard plates (echinoderms - sea urchins & starfish).The "shell" of a sea urchin (its "test") appears to be an exoskeleton, but technically its an endoskeleton because it is covered with a thin layer of living fleshy tissue.
Know the types of muscle contraction
Three Types of Muscle: 1.Cardiac - involuntary muscle of the heart. 2.Smooth - involuntary muscles of the internal organ systems (except the heart). 3.Skeletal - voluntary muscles attached to the skeletal system for movement & locomotion
How do neurons communicate at the synapses? What happens if you get botulism? S20
•Neurons Communicate at Synapses. Synapse - a physical junction or relay point between the endings of the "sending neuron" and the "receiving cell". Receiving cells can be another neuron, an effector cell or an endocrine cell. 1.Action potential arrives at synaptic terminal. 2.Action potential causes some synaptic vesicles filled with neurotransmitter to fuse with plasma membrane of synaptic terminal; Neurotransmitter is released into synaptic cleft. 3.Neurotransmitter diffuses across synaptic cleft & binds to ion channel receptor proteins in receiving cell dendrite membrane. 4.An influx of (Na+) ions may trigger an action potential in the receiving cell. 5.Neurotransmitter is taken back into sending neuron (or is degraded or diffuses away) & ion channels close. • •From before - the role of Ca2+ ions: When impulse arrives at axon endings, Ca channels open, an influx of Ca results, rise in internal Ca levels stimulates synaptic vesicles to fuse w/presynaptic plasma membrane. •Strychnine is a competitive antagonist of glycine, an important inhibitory neurotransmitter in the spinal cord, brainstem, and higher center. It antagonizes the inhibitory tone, resulting in powerful and uncontrollable muscle contractions. •The width of a synaptic cleft is approx. 20 nm; the thickness of an average lipid bilayer is about 5 nm.
What is a good example of adaptive immunity?
•Vaccinations Are A Great Example of "Adaptive Immunity" Individuals are injected with a "vaccine" (or infected with a pathogen). Vaccines are comprised of dead or attenuated pathogens (or fragments). Immune system builds up a first-time defense to the pathogen. Includes production of antibodies & specific "memory" lymphocytes. Immune system protects against future infections or attacks by the same pathogen. •Child being vaccinated (for HPV?); Military vaccination against smallpox; child with chickenpox & closeup of chicken pox lesions/pustules containing virus. •Common childhood vaccinations include chicken pox (varicella), measles, mumps, rubella (often provided in a single shot/vaccination); Diphtheria, tetanus, and pertussis (DTaP) also frequently given in a single shot/vaccination. •Others include polio, rabies, smallpox, anthrax. •Chicken pox is spread by contact, breathing, sneezing, coughing etc.