Tissue level of organization

dreamer18's version from 2015-10-01 22:00

Section 1

Question Answer
4 basic types of tissues in the human body1. epithelial tissue 2. connective tissue 3. muscular tissue 4. nervous tissue
epithelial tissuecells arranged in continuous sheets in single or multiple layers, cells are closely packed together with little intercellular space between plasma membranes, avascular, has high rate of cell division and constantly renews and repairs itself
avacularlacks its own blood supply
who does an avascular tissue get blood supplyblood vessels that bring nutrients and remove wastes are in adjacent connective tissue and exchange substances by diffusion
3 major functions of epithelial tissueselective barrier, secretory surfaces, protective surfaces
selective barrierallows or limits substances into and out of the body
secretory surfacesrelease products produced by the cells
protective surfacesresist abrasive forces of environment
epithelial tissue plays a role inprotection, filtration, absorbtion, secretion and excretion
2 types of epithelial tissuecovering and lining epithelium, glandular epithelium
covering and lining epitheliumclassified by layers: simple, stratified, pseudostratified ; and classified by shapes: squamous, cuboidal, columnar, transitional
simplesingle layer of cells that function in diffusion, osmosis, filtration, secretion and absorption
stratified2 or more layers, protect underlying tissues where abrasive forces exist
pseudostratifiedappears to have multiple layers but is truly simple epithelium. all cells attach to basement membrane but not all reach apical surface
squamousflatened irregularly shaped cells, allow rapid passage of substances
cuboidalcube shaped cells, function in secretion and absorption
columnarelongated cells, protect underlying tissues, may have cilia or microvilli
transitionalcells change shape from flat to cuboidal and back.. urinary bladder: stretches, flattens when full

Section 2

Question Answer
simple squamouslocation: (endothelium) lines heart, blood and lymph vessels; (mesotheleum) form epithelial layer of serous membrane. Also found in air sacs of lungs. Function: filtration or diffusion
simple cuboidallocation: surface of ovary, capsule of lens of eye, lines kidney tubules and ducts of many glands function: secretion and absorption
simple columnarnon ciliated: lines G1 tract, ducts, glands and gallbladder-- function: secretion and absorption.. ciliated: lines bronchioles of respiratory tract, uterine uses, uterus--function: moves substances/mucus by ciliary action
pseudostratified columnarlocation: lines airways of respiratory tact, lines ducts of glands (can be ciliated or non ciliated) function: secretion and movement of mucus; absorption and protection
stratified squamousflattened/squamous cells on apical surface and may have cuboidal or columnar cells in deeper layers.. location: (kertinaized) superficial layer of skin, (nonkerartinied) lining in mouth, esophagus, vagina and tongue. function: protection against abrasion and microbes
stratified columnarseveral layers of shortened, irregularly shaped cells; only apical layer has elongated cells. Found: lines the urethra/esophogal glands. function: protection and secretion
glandular epitheliumfunction: epithelium is secretion, which is accomplished by glandular cells. Classified as either exocrine or endocrine.
glandsingle or group of cells that secrete substances into ducts, onto surface or into blood
exocrine glandssecrete substances into ducts that empty onto the surface of covering and lining epithelium-skin surface, lumen of a hollow organ
examples of exocrine glandssweat glands, salivary glands, digestive glands, pancreas
endocrine glandssecrete hormones into interstitial fluid which directly diffuse into the bloodstream (no ducts involved)
examples of endocrine glandspituitary, thyroid and adrenal glands

Section 3

Question Answer
connective tissueone of the most abundant tissues in the body, usually highly vascular (rich blood supply) consists of cells and extracellular matrix
connective tissue cellsfibroblasts, adipocytes, mast cells, white blood cells, macrophages, plasma cells
fibroblastslarge flat branching cells, most numerous, secrete fibers
adipocytesfat cells or adipose cells store tryglycerides (fat). Found around heart and kidney.
mast cellsproduce histamine
white blood cellsor Leukocytes are usually not found in high numbers
macrophagesengulf bacteria and cellular debris by phagocytes
plasma cellsdevelop from white blood cells, excrete antibodies
connective extracellular matrix consists ofground substance and fibers
ground substancebetween cells and fibers, supports and binds cells together, stores water, provides a medium for exchange of substances
3 types fibers1. collagen fibers 2. elastic fibers 3. reticular fibers
collagen fiberscollagen in parallel bundles, found in most connective tissue especially bones, cartilage, tendons and ligaments
elastic fiberssmaller than collagen, branchesd. strength, stability and elasticity (ability to stretch significantly then return to normal shape) found in skin, blood vessel walls and lungs
reticular fiberscontain collagen arranged in bundles with coating of glycoprotein .. found in stroma
types of connective tissueloose connective tissue, dense connective tissue
types of loose connective tissueareolar, reticular, adipose
areolar connective tissuemost widely distributed connective tissu in the body, contains several kinds of cells: fibroblasts, macrophages, plasma cells, mast cells & adipocytes.. has 3 types of fibers: collagen, elastic, reticular.. Location: forms subcutaneous layer of tissue deep to skin; around the blood vessels, nerves, and bidy organ Function: strength, elasticity, support
reticular connective tissueFine interlacing network of reticular fibers. Location: stroma of liver, spleen, lymph nodes. Function: forms the stroma of organs; binds smooth muscle tissue celss
adipose tissuefibroblasts (called adipocytes): specialized cells that store triglycerides. Location: subcutaneous layer deep to skin, around heart and kidneys. Function: reduces heat loss through skin; serves as an energy reserve.
types of dense connective tissueregular, irregular, elastic
dense regular connective tissuecollagen fibers in bundles, Location: forms tendons, most ligaments and aponeurons Function: provides strong attachment between various structures
irregular dense connective tissuelocation: fascia (tissue that surrounds muscles, organs), joint capsules, dermis of skin Function: provides pulling strength
elastic connective tissueContains mostly fibroblasts and elastic fibers. location: lung tissue, walls of arteries, trachea, bronchial tubes, vocal cords Function: allows stretching of organs

Section 4

Question Answer
cartilagedense network of collagen or elastic fibers embedded in firm ground substance (chondroitin sulfate), collagen fibers give it strength and resilience (ability to resume original shape)
chondrocytesmature cells located in lacunae
lacunaesmall spaces between lamellae and contain osteocytes
perichondriumdense irregular connective tissue that covers cartilage, cartilage's only nerve supply
growth and repair occur slowly because cartilage isavascular
3 types of cartilagehyaline cartilage, fibrocartilage, elastic cartilage
hyaline cartilagelocation: end of bones, nose, larynx, bronchi Function: provides smooth surface of movement at joints, flexability
fibrocartilageHas chondracytes among collagen. location: intervertebral discs, menisci of knee, pubic symphysis. Function: support and joining structures togehter
elastic cartilageHas chondracytes. location: top of larynx, external ear and auditory tubes Function: strength and elastcity; maintains certain structures

Section 5

Question Answer
bone tissueeither compact (consists of osteons that contain lamellae, osteyocytes, cacaliculi, and central canals) or spongy (contain trabeculae and filled with bone marrow)
compact bonebasic unit: osteon or haversion system with 4 parts
4 parts of osteonlamellae, lacunae, canaliculi, central haversian canal
lamellaeconcentric rings made of mineral salts (give bone strength)
lacunaespaces between lamellae that contain osteocytes
osteocytesmature bone cells
canaliculinetworks projecting from lacunae that provide routes from nutrients to reach osteocytes and wastes to leave them
central haversian canalcontains blood and lymph vessels and nerves
spongy bonelacks osteoons, but has columns of bone called trabeculae.. contains lamellae, osteocytes, lacunae and canaliculi
trabeculaecolumns of bone in spongy bone

Section 6

Question Answer
muscular tissueconsists of elongated cells called muscle fibers or mytocytes, can use ATP to generate force, produces movements, maintains posture, generates heat and provides protection
myocyteselongated cells (muscle fibers)
3 types of muscular tissueskeletal, cardiac and smooth
skeletal musclelong striated fibers, many nuclei located at periphery, voluntary control, only muscle that has multiple nuclei, striated
cardiac musclebranched striated fibers, one centrally located nucleus, involuntary, different from other muscles because it has: intercalated discs.. located in heart wall and pumps blood to all parts of the body
intercalated discsthickenings of plasma membrane that hold fibers together and provide route for quick conduction between muscle fibers
smooth musclenonstriated fibers with one centrally located nucleus, involuntary control, function: motion (construction of blood vessels and airways), propulsion of food through G1 tract, contraction of urinary bladder and gallbladder, movement of substances through whatever it is linig

Section 7

Question Answer
nervous tissueconsists of 3 parts: cell body, dendrites, axon
cell bodycontains nucleus and other organelles (of nervous tissue)
dendritesshort cell extensions that receive impulses from receptor or previous neuron
axona single thin cell extension that conducts nerve impulses away from the cell body