Anatomy Lecture Ch 4 Review Questions Flashcards
What are the four basic tissue types?
epithelial, muscular, connective, nervous
What does epithelial tissue do?
covers body surfaces; lines hollow organs, body cavities and ducts; forms glands; allows body to interact with internal and external environments
What does connective tissue do?
protects and supports the body and its organs, binds organs together, stores energy reserves as fat, helps provide the body with immunity to disease-causing organisms
What does muscular tissue do?
composed of cells specialized for contraction and generation of force which generates heat that warms the body
What does nervous tissue do?
detects changes in a variety of conditions inside and outside the body and responds by generating electrical signals called nerve action potentials that activate muscular contractions and glandular secretions
What is a biopsy?
the removal of a sample of living tissue for microscopic examination
What are cell juntions?
contact points between the plasma membranes of tissue cells
What are the five main types of cell junctions?
tight junctions, adhering junctions, desmosomes, hemidesmosomes, and gap junctions
What is the structure of tight junctions?
consist of weblike strands of transmembrane proteins
What do tight junctions do?
inhibit the passage of substances between cells and prevent the contents of these organs from leaking into the blood or surrounding tissues
Where are tight junctions located?
stomach, intestines, and urinary bladder
What is the structure of adhering junctions?
contain plaque, a dense layer of proteins on the inside of the plasma membrane that attaches both to membrane proteins and to microfilaments of the cytoskeleton
What are cadherins?
transmembrane glycoproteins that insert into the plaque of adhering junctions, partially crossing the intercellular space, and connects to cadherins of an adjacent cell
What are adhesion belts?
extensive zones formed from adhering junctions that encircle the cell
What do adhering junctions do?
help epithelial surfaces resist separation during various contractile activities, such as food moving through the intestines
What is the structure of desmosomes?
contain plaque and have cadherins that extend into the intercellular space between adjacent cell membranes and attach cells to one another; plaque does not attach to microfilaments but instead to intermediate filaments
What are intermediate filaments made of?
the protein keratin
Where are desmosomes most common?
cells that make up the epidermis and among cardiac muscle cells
What is the function of desmosomes?
prevent epidermal cells from separating under tension and cardiac muscle cells from pulling apart during contraction
How are hemidesmosomes different from desmosomes?
they do not link adjacent cells
What are the transmembrane glycoproteins in hemidesmosomes called?
integrins
What do hemidesmosomes do?
anchor cells to the basement membrane but not to one another
What is the structure of gap junctions?
membrane proteins called connexins form tiny fluid-filled tunnels called connexons that connect neighboring cells
What do gap junctions do?
allow ions and small molecules to diffuse from the cytosol of one cell to another through connexons while preventing the passage of large molecules; allow the cells in a tissue to communicate with one another; enable nerve or muscle impulses to spread rapidly among cells
How are cells arranged in epithelial tissue?
tightly packed with little or no extracellular matrix
How are cells arranged in connective tissue?
a large amount of extracellular matrix separates cells that are usually widely scattered
What are the differences in blood vessels between epithelial and connective tissue?
epithelial tissue has no blood vessels; connective tissues have significant networks of blood vessels which contain and distribute almost all the blood vessels in the body
What is epithelial tissue?
consists of cells arranged in continuous sheets, in either single or multiple layers
What are the two general types of epithelial tissue?
surface epithelium and glandular epithelium
What does surface epithelium do?
forms the outer covering of the skin and some internal organs and the inner lining of structures
Where is surface epithelium found besides the skin?
blood vessels, ducts, body cavities, and the lining of the respiratory, digestive, urinary, and genital systems
What does glandular epithelium do?
makes up the secreting portion of glands
Where is glandular epithelium found?
thyroid gland, suprarenal glands, sweat glands, digestive glands
What does epithelial tissue do?
protects, secretes (mucus, hormones, enzymes), absorbs nutrients in the digestive canal, and excretes various substances in the urinary tract
Where is the apical surface of an epithelial cell located?
facing the body surface, a body cavity, the lumen (interior space) of an internal organ, or a tubular duct
Where is the lateral surface of an epithelial cell located?
faces the adjacent cells on either side
What types of junctions do lateral surfaces of epithelial cells contain?
tight junctions, adhering junctions, desmosomes, gap junctions
Where is the basal surface of epithelial cells located?
opposite of the apical surface
What is the basement membrane?
a thin extracellular layer that commonly consists of two layers
What are the two layers of the basement membrane?
basal lamina and reticular lamina
What is the basal lamina?
closest to, and secreted by, the epithelial cells, contains proteins such as laminin and collagen as well as glycoproteins and proteoglycans
What do laminin molecules in the basal lamina do?
adhere to integrins in hemidesmosomes and attach epithelial cells to the basement membrane
What is reticular lamina?
closer to the underlying connective tissue and contains proteins such as collagen produced by fibroblasts in connective tissue
What are the functions of the basement membrane?
attaching to and anchoring the epithelium to its underlying connective tissue, forming a surface along which epithelial cells migrate during growth or wound healing, restrict passage of larger molecules between epithelium and connective tissue, and participate in filtration of blood in the kidneys
What happens when epithelial tissue combines with nervous tissue?
forms special organs for smell, hearing, vision, and touch
What are the 3 types of arrangements in cell layers?
simple epithelium, pseudostratified epithelium, stratified epithelium
What is simple epithelium?
a single layer of cells
What are the functions of simple epithelium?
diffusion, osmosis, filtration, secretion, absorption
What is secretion?
the production and release of substances sch as mucus, sweat, or enzymes
What is absorption?
the intake of fluids or other substances such as digested food from the intestinal tract
What is pseudostratified epithelium?
appears to have multiple layers of cells because the cell nuclei lie at different levels and not all cells reach the apical surface; is actually a simple epithelium because all its cells rest on the basement membrane
What are the functions of pseudostratified epithelium?
cells that do extend to the apical surface may contain cilia, others secrete mucus
What is stratified epithelium?
two or more layers of cells
What is the function of stratified epithelium?
protects underlying tissues in locations where there is considerable wear and tear
What are the 4 types of epithelial cell shapes?
squamous, cuboidal, columnar, transitional
What are squamous cells?
thin, flat cells which allow for the rapid passage of substances through them
What are cuboidal cells?
shaped like cubes or hexagons, may have microvilli at their apical surface and function in either secretion or absorption
What are columnar cells?
shaped like columns, protect underlying tissues, apical surfaces may have cilia or microvilli and are often specialized for secretion or absorption
What are transitional cells?
change shape from squamous to cuboidal and back, as organs of the urinary system such as the bladder stretch and collapse
What are the 4 major types of simple epithelium?
simple squamous epithelium, simple cuboidal epithelium, simple columnar epithelium, pseudostratified columnar epithelium
What are the two types of simple squamous epithelium?
endothelium which lines the heart, blood vessels, and lymphatic vessels and mesothelium which forms the epithelial layer of serous membranes
What are the four types of stratified epithelium?
stratified squamous epithelium, stratified columnar epithelium, stratified columnar epithelium, urothelium/transitional epithelium
What is the function of glandular epithelium?
secretion
What is a gland?
consists of epithelium that secretes substances into ducts, onto a surface, or eventually into the blood in the absence of ducts
What are the two types of glands?
endocrine and exocrine
What do endocrine glands secrete?
hormones
How do endocrine glands secrete hormones?
hormones enter the interstitial fluid and then diffuse into the bloodstream without flowing through a duct
How do exocrine glands secrete?
using ducts that empty onto an epithelium that covers or line a surface, such as the skin surface or the lumen of a hollow organ
What are the two classifications of exocrine glands?
unicellular and multicellular
How are multicellular glands categorized?
whether their ducts are branched or unbranched and the shape of the secretory portions of the gland
What are the 5 types of simple glands?
simple tubular, simple branched tubular, simple coiled tubular, simple acinar, simple branched acinar
What are the 3 types of compound glands?
compound tubular, compound acinar, compound tubuloacinar
How do merocrine glands work?
secretions are synthesized on ribosomes attached to rough ER; processed, sorted, and packaged by the Golgi complex; and released from the cell in secretory vesicles vis exocytosis
How do apocrine sweat glands work?
accumulate their secretory product at the apical surface of the secreting cell; that portion of the cell pinches off by exocytosis from the rest of the cell to release the secretion
How do holocrine glands work?
the cells of holocrine glands accumulate a secretory product in their cytosol; as the secretory cell matures, it ruptures and becomes the secretory product
What type of gland is a sebaceous gland?
holocrine gland
What type of gland is a salivary gland?
merocrine
What are the functions of connective tissues?
binds together, supports, and strengthens other body tissues; protects and insulates internal organs; compartmentalizes structures such as skeletal muscles; serves as the major transport system within the body; contains and distributes almost all the blood vessels in the body; is the primary location of stored energy reserves; main source of immune responses
What two materials make up the extracellular matrix of connective tissues?
protein fibers and ground substance
What type of cells give rise to the cells of connective tissue?
mesenchymal cells
What are immature cells in loose and dense connective tissue called?
fibroblasts
What are immature cells in cartilage called?
chondroblasts
What are immature cells in bone called?
osteoblasts
What do -blast cells do?
retain the capacity for cell division and secrete the extracellular matrix
What are mature -cyte cells responsible for?
monitoring and maintaining the extracellular matrix
What are fibroblasts?
large, flat cells with branching processes present in all the general connective tissues
What are macrophages?
phagocytes that develop from monocytes, a type of white blood cell
What are resting macrophages?
resides in a particular tissue
What are wandering macrophages?
have the ability to move throughout the tissue and gather at sites of infection of inflammation to carry on phagocytosis
What are plasmocytes?
plasma cells
What are mast cells/mastocytes?
involved in the inflammatory response, the body’s reaction to injury or infection, and can also bind to, ingest, and kill bacteria
What are adipocytes?
connective tissue cells that store triglycerides/fats
What are leukocytes?
white blood cells; not found in significant numbers in normal connective tissue but migrate into connective tissue in response to certain conditions
What are reticular fibers?
fibers made of collagen and glycoproteins that provide support in blood vessel walls and form branching networks around various cells
What are collagen fibers?
strong, flexible bundles of the protein collagen, the most abundant protein in the body
What is ground substance?
the material between cells and fibers that is made of water and organic molecules; supports cells and fibers, binds them together, and provides a medium for exchanging substances between blood and cells
What are neutrophils?
white blood cells that migrate to sites of infection to destroy microbes by phagocytosis
What are eosinophils?
white blood cells that migrate to sites of parasitic infection and allergic responses
What are glycosaminoglycans?
polysaccharides including hyaluronic acid, chondroitin sulfate, dermatan sulfate, and keratan sulfate
What do proteoglycans do?
form a core protein
What is hyaluronic acid?
a viscous, slippery substance that binds cells together, lubricates joints, and helps maintain the shape of the eyeballs
What does chondroitin sulfate do?
provides support and adhesiveness in cartilage, bone, skin, and blood vessels
Where is dermatan sulfate located?
skin, tendons, blood vessels, and heart valves
Where is keratan sulfate located?
bone, cartilage, and the cornea of the eye
What do adhesion proteins do?
link components of the ground substance to one another and to the surfaces of cells
What does fibronectin do?
binds to both collagen fibers and ground substance, linking them together; also attaches cells to the ground substance
What are the three types of fiber in the extracellular matrix of connective tissues?
collagen fibers, elastic fibers, and reticular fibers
What do collagen fibers do?
resist pulling or stretching while also allowing tissue flexibility
What do elastic fibers do?
branch and join together to form a fibrous network allows for stretching, strength, and stability
What do reticular fibers do?
arranged in fine bundles with a coating of glycoprotein, provide support in the walls of blood vessels and form a network around the cells in some tissues, forms the stroma of many soft organs and help form the basement membrane
What is the stroma?
supporting framework of organs
What are the 2 types of embryonic connective tissue?
mesenchyme and mucoid connective tissue
What are the 3 types of loose connective tissue?
areolar, adipose, reticular
What are the 3 types of dense connective tissue?
dense regular, dense irregular, elastic
What are the 3 types of supporting connective tissue cartilage?
hyaline cartilage, fibrous cartilage, elastic cartilage
What are the 2 types of bone tissue?
compact and spongy
What are the 2 types of liquid connective tissue?
blood and lymph plasma
What is cartilage lacunae?
spaces in the extracellular matrix where chondrocytes occur
What is the perichondrium?
a covering of dense irregular connective tissue that surrounds the surface of most cartilage and contains blood vessels and nerves and is the source of new cartilage cells
What is interstitial growth?
growth of cartilage from within the tissue; the cartilage increases rapidly in size due to the division of existing chondrocytes and the continuous deposition of increasing amounts of extracellular matrix by the chondrocytes
What is appositional growth?
growth at the outer surface of the tissue; cells in the inner cellular layer of the perichondrium differentiate into chondroblasts which surround themselves with extracellular matrix and become chondrocytes
What are membranes?
flat sheets of pliable tissue that cover or line a part of the body
What are epithelial membranes?
consist of an epithelial layer and an underlying connective tissue layer
What is a mucous membrane?
lines a body cavity that opens directly to the exterior
What is the lamina propria?
the areolar connective tissue layer of a mucous membrane
What is a serous membrane?
lines a body cavity that does not open directly to the exterior and covers the organs that are within the cavity; consist of areolar connective tissue covered by mesothelium
What are the two layers of serous membranes?
parietal layer and visceral layer
What is the parietal layer of serous membranes?
the layer attached to and lining the cavity wall
What is the visceral layer of serous membranes?
the layer that covers and adheres to the organs within the cavity
What is serous fluid?
a watery lubricant secreted by the mesothelium of a serous membrane that allows organs to glide easily over one another or to slide against the walls of cavities
What is the serous membrane lining the thoracic cavity and covering the lungs called?
pleura
What is the serous membrane lining the heart cavity and covering the heart called?
pericardium
What is the serous membrane lining the abdominal cavity and covering the abdominal organs called?
peritoneum
What is the cutaneous membrane?
the skin
What are synovial membranes?
line the cavities of partially to freely movable joints
What does synovial fluid do?
lubricates and nourishes the cartilage covering the bones at movable joints and contains macrophages that remove microbes and debris from the joint cavity
What is muscular tissue?
consists of elongated cells called muscle fibers or myocytes that can use ATP to generate force
What two cells comprise nervous tissue?
neurons and neuroglia
What do neurons do?
convert stimuli into electrical signals called nerve action potentials and conduct these action potentials to other neurons, to muscle tissue, or to glands
What three parts do neurons consist of?
cell body, dendrites, axons
What is contained within the cell body of a neuron?
the nucleus and organelles
What are dendrites?
tapering, highly branched, usually short cell processes that are the major input portion of a neuron
What are axons?
a single, thin, cylindrical process that may be very long that is the output portion of a neuron, conducting nerve impulses toward another neuron or to some other tissue
What do neuroglia do?
do not generate or conduct nerve impulses but have many important supportive functions
What are excitable cells?
cells that exhibit electrical excitability which is the ability to respond to certain stimuli by producing electrical signals such as action potentials
What is tissue repair?
the replacement of worn-out, damaged, or dead cells
What is the stroma?
supporting connective tissue
What is the parenchyma?
cells that constitute the functioning part of the tissue or organ
What is granulation tissue?
an actively growing connective tissue
What three factors affect tissue repair?
nutrition, blood circulation, and age
