A&P Tissue Level of Organization
Stratified squamous epithelium
- 2 or more layers - forms superficial layer of skin, lines wet surfaces (lining of mouth, esophagus, parts if epiglottis, part of pharynx, and vagina) and covers tongue - Protection against abrasion, water loss, UV radiation, and foreign invasion
General Features of Epithelial Tissue
- Cells are arranged in sheets - Cells are densely packed - Many cell junctions are present - Epithelial cells attach to a basement membrane - Epithelial tissue is avascular but does have a nerve supply - High turnover rate (protective); hence Mitosis occurs frequently
Dense Irregular connective tissue
- Coiled bundles of collagen fibers, and a few Fibroblasts - able to withstand force acting on it in different directions Location: - dermis of skin - muscle covering - joint capsules - periosteum
4 basic types of tissues
- Epithelial - Connective - Nervous - Muscular
Epithelial VS Connective tissue
- Epithelial tissue has many cells tightly packed together and little to no extracellular matrix - Connective tissue with very few scattered cells surrounded by large amounts of extracellular matric
Reticular loose connective tissue
- Has plenty of reticular fibers (extremely fine collagen III fibers) that form a network to support soft delicate organs such as Spleen, Tonsils, Lymph nodes. - Reticulocytes (Fibroblastic cell) maintain this connective tissue
Spongey bone tissue
- Lacks Osteons - contains trabeculae (honeycomb network) - Irregularly arranged lamella with osteocytes - Osteocytes interconnected by canaliculi (nutrient flow from vasculature in endosteal surface)
Connective tissue characteristics
- Most abundant, widely distributed tissues in the body; supports, binds, insulates, protects, and provides the medium of transport of molecules and ions within the body - cells make large quantities of ECM - highly vascular and is innervated (except cartilage) - all derived from Mesenchyme cells
Exocrine glands
- Secrete their products into ducts that empty onto surface of a covering and lining epithelium such as the skin surface or the lumen of a hollow organ Location: - sweat, oil, and earwax glands of skin; digestive glands such as salivary glands (secrete into mouth cavity) and pancreas (secretes into small intestine) Function: - Produce substances such as sweat to help lower body temperature, oil, earwax, saliva, or digestive enzymes
Pseudostratified columnar epithelium
- ciliated variety lines airways of most of upper respiratory tract - secretes mucus that traps foreign particles, and cilia sweep away mucus for elimination from body
Smooth muscle
- involuntary - NO striations - spindle-shaped - iris of eyes, airway to lungs, stomach, intestines, gallbladder, urinary bladder, and uterus Function: - motion (constriction)
Transitional epithelium
- lines urinary bladder and portions of ureters and urethra - allows urinary organs to stretch and maintain protective lining while holding variable amounts of fluid without rupturing
Areolar Loose Connective tissue
- most abundant connective tissue - fibers are loosely organized in a fluid ground substance - called the "packing material" as it is used for insulating most of the internal organs Location: - Hypodermis, below mucous membrane; visceral and parietal membranes of the thoracic and abdominal cavities.
simple squamous epithelium
- single layer - found in air sacs of lungs, glomerular capsule of kidneys, inner surface of tympanic membrane (eardrum) - present at sites of filtration or diffusion, and at site of secretion in serous membranes - not found in areas subject to wear and tear
simple columnar epithelium
- single layer of columnlike cells - lines gastrointestinal tract, ducts of glands, and gallbladder - higher level of secretion and absorption
simple cuboidal epithelium
- single layer of cube-shaped cells - covers surface of ovary; anterior surface of capsule of lens of the eye; ducts of glands - secretion and absorption
Cardiac muscle
- striations - involuntary - intercalated discs - heart wall Function: - pumps blood to all parts of the body
Skeletal muscle
- voluntary - striations - usually attached to bones by tendons Function: - motion, posture, heat production, protection
Adipose loose connective tissue
:- Consists of Adipocytes ( Fat-cells) that store Triglyceride (neutral fat). - There is very little ECM, but there are plenty of blood vessels in the tissue. Location: - Under the skin (sub-cutaneous layer of fat in Hypodermis); in-between muscles, around Heart and Kidney, yellow bone marrow; female breast Function: - Heat conservation, food storage, support, insulation
Which tissue type consists of densely packed cells that are large and round, and have their nuclei pushed to one side?
Adipose
All of the following are considered primary (basic) tissue types except __________.
Bone - Epithelial, connective, and muscle are considered primary (basic) tissue types - bone is an example of connective tissue
Dense Regular connective tissue
Bundles of Collagen fibers ( white fibers) alternate with rows of Fibroblasts Location: - tendon: connects muscle to bone - ligament: connects bone to bone - aponeuroses: sheet-like tendons that attach muscles to muscles, or muscles to bones
The functions of connective tissue include all of the following except __________.
COMMUNICATION support protection bind structures together
Which of the following tissues is avascular (lacks a blood supply)?
Epithelium (CORRECT) Bone Dermis of skin Adipose tissue
This is the toughest kind of cartilage. It is found in places that receive a lot of mechanical stress
Fibrocartilage
Which tissue makes up the intervertebral discs between vertebrae?
Fibrocartilage
Endocrine glands
HORMONES - Diffuse directly into the bloodstream without flowing through a duct Location: - Pituitary gland at base of brain, pineal gland in brain, thyroid and parathyroid glands near larynx (voice box), adrenal glands superior to kidneys, pancreas near stomach, ovaries in pelvic cavity, testes in scrotum, thymus in thoracic cavity Function: - Hormones regulate many metabolic and psychological activities to maintain homeostasis
Epithelial membranes: Cutaneous membranes
Made of Epidermis and Dermis. Epidermis forms a dry protective covering for the body. - SKIN
Which tissue type forms the hip bone?
Osseous tissue (CORRECT) Skeletal muscle Fibrocartilage Dense regular connective tissue
Which tissue type lines the small intestine, where secretion of digestive enzymes and absorption of nutrient building blocks occurs?
Simple columnar epithelium (CORRECT) Pseudostratified columnar epithelium Simple squamous epithelium Stratified squamous epithelium
This tissue can look like the hexagonal tiles of a bathroom floor. It also forms the air sacs of the lungs.
Simple squamous epithelium
Which tissue lines the air sacs of the lungs and is ideal for diffusion of respiratory gases?
Simple squamous epithelium (CORRECT) Stratified squamous epithelium Simple cuboidal epithelium Simple columnar epithelium
Which of the following muscle tissues allow you to direct your eyeballs?
Skeletal - Skeletal muscle is the only muscle type that is voluntarily controlled
The shape of a smooth muscle cell can best be described as __________.
Spindle shaped - They are also non-striated (smooth in appearance) and uninucleate cells, which are under involuntary control.
Which tissue makes up the epidermis of skin and functions to protect underlying tissues from abrasion?
Stratified squamous epithelium (CORRECT) Simple squamous epithelium Dense irregular connective tissue Transitional epithelium
Blood is a type of connective tissue.
TRUE
In which of the following locations would dense regular connective tissue be found?
Tendon (CORRECT) Spleen Dermis Larynx
tissue
a group of cells that usually have a common embryonic origin and function together to carry out specialized activities
Blood tissue
a highly specialized liquid Connective tissue which acts as the medium of transport of molecules and ions within the body. It has a liquid ECM called Plasma in which 3 types of cells are suspended, RBCs, WBCs and Blood-platelets. White blood cells are specialized to defend the body against infection and disease.
Gland
a single cell or mass of epithelial cells adapted for secretion
Simple columnar epithelium functions in
absorption and secretion.
This type of connective tissue is primarily composed of cells.
adipose (CORRECT) hyaline cartilage blood bone
Collagen fibers
also called white fibers are made of Collagen protein. They resist pulling forces and provide flexibility. They are usually organized into tight bundles in the connective tissue. Bones, Cartilages, Ligaments and Tendons all have plenty of Collagen fibers.
Elastic fibers (yellow fibers)
are made of Elastin protein; elastin molecules are surrounded by a glycoprotein called Fibrillin. Elastic fibers provide elasticity to connective tissue, and is seen in Skin, wall of Blood vessels, and lung tissue
Osteons
are the units of compact bone tissue. Each Osteon has a Central canal, and bone cells arranged around it in circles.
Squamous epithelial cells ________.
are thin and flat, like fish scales
This type of connective tissue is found under epithelia, packaging organs, and surrounding capillaries.
areolar
Select the tissue that is a simple epithelium.
areolar transitional pseudostratified (CORRECT) dense regular
This connective tissue is made of hard calcified matrix and stores calcium and other minerals.
bone (osseous tissue)
Nervous tissue is made up of __________.
both neurons and neuroglia - The neuroglia protect, support, and insulate the more delicate neurons. The neurons are specialized to receive stimuli and conduct impulses throughout the body.
________ muscle cells consist of branched uninucleate cells with junctions called as intercalated discs.
cardiac
The most widespread tissue in the body is __________.
connective tissue
This is the most abundant and widely distributed tissue type in the body.
connective tissue
General characteristics of Muscular tissue
consists of fibers that can shorten or contract and so the are critical components to provide motion, maintain posture, and produce heat 3 types: - cardiac - skeletal - smooth
Muscular tissue function
contractile; mainly for movement
This tough, strong, connective tissue is found beneath the epithelial tissue of the skin. It is packed with collagen fibers that run in all different directions.
dense irregular
This connective tissue is packed with parallel collagen fibers, attaches muscles to bone, and can withstand great stress when pulled in one direction.
dense regular
Which statement regarding neuroglia is FALSE? Neuroglia __________
do not have nuclei (CORRECT) are part of brain tissue support cells in the nervous system include special insulating cells
Secretion of exocrine glands
enter ducts that empty onto the surface of a covering/lining epithelium such as the skin surface or the lumen of the stomach
Secretion of endocrine glands
enter the interstitial fluid and diffuse into the blood stream
This tissue type is a covering and lining tissue. It also includes glands.
epithelial
A distinguishing feature of connective tissue is the __________.
extracellular matrix (CORRECT) cell size cell arrangement cell thickness
Elastic cartilage
has plenty of elastic fibers and chondrocytes; seen in areas that show elasticity - provides strength and elasticity; maintain shape of certain structures Location: - external ear - epiglottis
Fibrocartilage
has think bundles of collagen fibers and Chondrocytes; can resist high compressional force - strongest type of cartilage Location: - intervertebral disc - pubic symphysis - knee-meniscus
Cartilage tissue
is a flexible but tough connective tissue formed by Chondroblasts. It has a dense network of Collagen or elastic fibers embedded in the ECM, which consists of Water (80%) and Chondroitin sulfate - avascular, not innervated
What additional component associated with outer skin epithelium is not seen in oral epithelium?
keratin (CORRECT) basal lamina nerve fibers blood vessels
Fibroblasts
large flat cells that move through connective tissue and secrete fibers and ground substance
All the following are examples of connective tissue EXCEPT __________.
ligaments neurons (CORRECT) tendons bones
Epithelial membranes: Serous membranes
lines a body cavity that does not open directly to the exterior; it forms a double layered , bag-like covering for the visceral organs; Pericardium for heart, Pleura for lungs and Peritoneum for the abdominal organs; each has a parietal layer and a visceral layer with a fluid in-between
Synovial membranes
lines the cavities of movable joints ( Synovial joints); these are made of areolar and adipose connective tissues ( no epithelial tissue). Synovial membrane secretes the synovial fluid ( mostly Hyaluronic acid and water) that lubricates the movable joints.
A unique histological feature of neurons is the appearance of __________.
long extensions
Reticular fibers
made of collagen and glycoproteins. - Provide support in blood vessel walls and form branching networks around various cells
Elastic connective tissue
mainly consists of elastic fibers with fibroblasts Location: - lung tissue - wall of arteries - vocal cords - strong and can recoil to original shape after being stretched
Epithelial tissue function
mainly covering tissue
Connective tissue function
mainly supporting tissue
Nervous tissue function
make uo the brain, spinal cord, and nerves; mainly for coordination
All connective tissue is derived from an embryonic tissue known as __________.
mesenchyme
Hyaline cartilage
most abundant cartilage tissue - weakest type of cartilage and can be fractured Location: - tracheal region - articular cartilage - costal rib - tip of nose - fetal skeleton
The functions of epithelial tissue include all of the following except __________.
movement (CORRECT) secretion absorption protection
This primary tissue type generates electrical signals and can actively contract.
muscle
All of the following are examples of connective tissue except __________.
muscle (CORRECT) blood bone cartilage - Muscle is an example of muscle tissue, which includes skeletal, cardiac, and smooth muscle types.
The support cells found in nervous tissue are called ________.
neuroglia
________ are cells that make up the brain and spinal cord and transmit electrical signals from receptor to effectors.
neurons
The shapes of epithelial cells include all of the following except __________.
oblique (CORRECT) squamous columnar cuboidal
Simple epithelia have ________.
one type of epithelial cell, arranged in a single layer
Dense regular connective tissue is composed primarily of __________.
parallel collagen fibers (CORRECT) - This arrangement provides this tissue with the ability to withstand great tensile stress when pulling force is applied in one direction. This tissue is found within tendons, aponeuroses, and most ligaments.
Stratified squamous epithelium consists of many layers of cells, ideal for
physical protection against abrasion
Epithelial cells are specialized to ________.
receive stimuli and conduct electrical signals to all parts of the body protect, support, and bind together other tissues actively contract and produce many types of movements secrete, filter, and absorb (CORRECT)
Example of a holocrine gland
sebaceous gland of the skin
Simple cuboidal epithelium functions in
secretion and absorption.
All of the following are types of muscle tissue except __________.
squamous (CORRECT) smooth skeletal cardiac
All of the following are examples of the arrangement or relative number of layers of epithelial tissues except __________.
striated (CORRECT) simple stratified pseudostratified
A common and distinguishing feature of both skeletal and cardiac muscle tissue is the appearance of __________.
striations - Striations (stripes) are alternating light/dark bands found in skeletal and cardiac muscle tissue. They are due to the alignment of myofibrils within muscle cells.
Epithelial membranes: Mucous membranes
this lines a body cavity that opens to the exterior; goblet cells secrete mucus. e.g. moist lining of the digestive, respiratory and reproductive system .
Groups of similar cells that share a function are called __________.
tissues
This tissue type is capable of changing its shape and stretching. It lines the urinary bladder and ureters.
transitional epithelium