A&P: Tissue Level of Organization Flashcards
4 Types of Tissues
Epithelial / Connective / Muscular / Nervous
Epithelial Tissue
protective AND selective barrier that covers body surfaces and lines hollow organs
secretory that forms parts of glands
own nerve supply but avascular
Connective Tissue
protect, supports, binds organs, energy storage, provide immunity
highly vascular
most abundant and widely distributed
Muscular Tissue
generate physical force for movement
generate body heat
Nervous Tissue
detect changes in body and respond by generating nerve impusles
Cell Junctions
contact points between plasma membrane of tissue cells
Tight Junctions
tight, water proof connections
ex) stomach, intestines, bladder
transmembrane proteins connecting
Adherens Junctions
resist separation during contractile activities
adhesion belt (plaque + microfilament, actin) and cadherin
Desmosomes
prevent cells from separation from each other; “spot weld”
plaque + intermediate filament (keratin), cadherin
Hemidesmosomes
anchor cells to Basement Membrane; not other cell
plaque + keratin, integrin to laminin
Gap Junctions
gaps allow for ions/electro/chemical signals for communication
connexons (multiple connexins)
ex) cardiac muscle
Surfaces of Surface Epithelial Cells
apical (free)
lateral
basal
Simple Squamous Epith
single layer, flat
filtration and diffusion
@ kidneys, blood vessels in lung
for rapid passage, needs to be flat…
Endothelium
type of simple squamous
lines cardiovascular and lymphatic sys
“endo-” = “within/inner”
Mesothelium
forms epithelial layer of serous membrane (thoracic cavities)
pericardium, pleura, peritoneum
“meso-“ = “middle, intermediate”
Simple Cuboidal Epith
secretion and absorption
for things to secrete, cant be flat…
Nonciliated Simple Columnar Epith w/ Microvilli
allows great absorption
ex) GI tract
Ciliated Simple Columnar Epith
moves mucus and particles over the surface; beats in unison
ex) Fallopian tube, respiratory tract
Stratified Squamous Epith
protection agains abrasion, water loss, UV, microbes
ex) vagina, skin
Transitional Epith
“urothelium”
allows organ/tract to be stretched and allows recoil/relaxed
ex) urinary tract
Glandular Epithelium
forms the secretory portion of glands
endocrine and exocrine
Endocrine Gland
secretes hormones; NO DUCT
secreted -> interstitial fluid -> bloodstream
Exocrine
secreted -> duct -> “outside” (surface or lumen of hollow organ)
ex) sweat, sebaceous, saliva, mammary
Merocrine Secretion
R ER -> GC -> exocytosis’d
ex) salivary gland
Apocrine Secretion
product gathers up -> part of cell pinched off as secretion -> cell repair follows
ex) mammary gland, sweat gland
Holocrine Secretion
cell division -> mature cell rupture as secretory product
ex) sebaceous gland
Extracellular Matrix
material located between connective tissue cells
protein fibers + ground substance
Fibroblasts
secretes components for Extracellular Matrix, fibers and ground substance
Ground Substance
fluid, semifluid, gelatinous, calcified
support and bind cells, store water, allow exchange btwn blood and cells
composed of water, proteins, and polysaccharides
Collagen Fibers
main structural protein
parallel bundles of collagen
cushioning effect
Elastic Fibers
elastic
elastin surrounded by fibrillin
Reticular Fibers
supporting mesh network in organs
glycoprotein coated collagen arranged in find bundles
Loose Connective Tissues
Areolar: “packing material/fill up”
Adipose: fat; insulation, cushion, energy storage
Reticular: structural part of organ
Dense Connective Tissues
dense regular: tendon/ligament
dense irregular: fascia
elastic: aorta
Areolar Connective Tissue
mixture of reticular, collagen, elastic fibers
“packing material”
loose CT; most widely distributed
Adipose Tissue
composed of adipocyte
fat; insulation, cushion, protection, energy storage
Reticular Connective Tissue
composed of reticular fiber
structural part of organ
Dense Regular Connective Tissue
tensile strength along 1 direction
@tendons, ligaments
Dense Irregular Connective Tissue
pulling strength in different directions
@fascia
Elastic Connective Tissue
contains elastic fibers; can recoil
@aorta
Cartilage
composed of collagen fibers and elastic fibers
lacks blood nerves or blood supply; slow repair
3 types: hyaline, fibrous, elastic
Chrondrocytes
cartilage cells found in lacunae
Perichondrium
covering of dense irregular connective tissue that surrounds cartilage
HAS nerves and blood vessels
Hyaline Cartilage
provide flexibility and support
@ends of bones; joints
Fibrocartilage
@ intervertebral discs / menisci, portions of tendon
Elastic Cartilage
provides strength and elasticity
@ external ear, epiglottis, auditory tubes
Bone Tissue
Liquid Connective Tissue
blood and lymph
Membrane (Epithelial Membrane)
epithelial tissue + connective tissue
Mucous, Serous, Cutaneous Membranes
Mucous Membrane
lines a cavity that opens directly to exterior
ex) digestive, respiratory, genital tracts
Serous Membrane
lines cavity that doesn’t open directly to exterior; covers organs within the cavity
ex) thoracic or abdominal cavities
Cutaneous Membrane
skin
Synovial Membrane
lines joints
lacks epithelium
Muscular Tissue
consists of muscle fibers (myocytes)
use ATP to generate force for: body movement, posture, generate heat, protection
skeletal, cardiac, smooth
Skeletal Muscle Tissue
long, cylindrical, striated fibers
ex) biceps, quads, etc.
Cardiac Muscle Tissue
branched, striated fibers
@heart
Smooth Muscle Tissue
nonstriated fibers, spindle-shape
@artery
Nervous Tissue
consists of Neurons and Neuroglia
electrical excitability, so action potential
