tissues Flashcards
what are the four primary tissues
1 epithelial
2 connective
3 muscle
4 nervous
epithelial
covers body surfaces
lines organs, body cavities and ducts
forms glands
connective
protects and supports the body and organs
keeps organs together
stores energy (fat)
immune function
muscle
movement
nervous
detects and respond to environment changes
ECF
fluid that doesn’t encompass fluid in the cells
ICF- fluid that fills the space btw tissue and cells
plasma- liquid portion of blood
how cells are held together ?
via cell junctions which are intercellular connections btw adjacent cell membranes 1 tight junctions 2 adherent junctions 3 desmosomes junctions 4 hemidesmosomes 5 gap junctions
thigh junctions
adjacent plasma membrane
intercellular space (small)
strands of trans protein
adherent junctions( anchoring)
adjacent
microfilament actin- adhesion belt
como la ebilla de la correa- transmembrane glycoprotein cadherin
helps epithelial Tx resist separation during mechanical activity
desmosomes (anchoring)
2X anchoring plague - comprised of intermediate filaments
transmembrane glycoproteins: Cadherins
arranged like spot welds
contributes to mechanical stability of the tissue (outer layer of skin and cardiac tissue)
hemidesmosomes (anchoring)
. hemidesmosome
Only one anchoring plague*
transmembrane glycoproteins: integrin
fasten cells to each other or to extracellular proteins (basement membrane proteins)
gap junction
have connexons composed of connexin
channel proteins of adjacent cells connect
allow direct cell-cell transfer of small molecules (electrical and chemical signals)
*calcium ions in heart muscle
snail gene
activations of this gene suppresses cadherin production leading to dysplasia- tumor- metatarsi
epithelial tissue
covering and lining of epithelium(barrier membrane)
glandular epithelial- secretions and absorption.
epithelial 10 general features
1.) tightly packed
2.) form sheets single or multiples
3.) two surfaces apical or basal
4,) numerous cell junctions
5.) avascular
6.) basement membrane
7.) nerves supply usually present
8.) High capacity for mitosis
9.) diverse origin
10.) diverse functions
structure of epithelium
epical surface- top surface
lateral surfaces- sides- stick together
basal surface- bottom
structure under cell ?
basal laminar- attaches to basal surface of cell
reticular laminar- rough
connective tissue
in btw all of these layers you can find nerves and and blood vessels.
types of arrangements of layers
simples- one layer
pseudostratified- nucleus of cells don’t align
stratified- multiples layers
types of cell shape
squamous- flat
cuboidal- square
columnar- skinny
what are the two types of glandular cell
exocrine and endocrine
exocrine
secretion substances into a duct or a free surface
mucous, sweat and sebum, enzimes
goblet cells
exocrine structural types
simple- unbranched compound- branched unicellular or multicellular shape tubular- spiral acinar- rounded tubuloacinar- both rounded and tubular
exocrine functional types
merocrine
apocrine
holocrine
merocrine
most glandular cells
sweat glands are in this group
nucleus- routh er- golgi- secretory vesicle out of cell- secretion
apocrine
pinched off cell is secretion- mammary glands are this type
holocrine
cell division replaces lost cell - mature cell dies and becomes secretory product example is sebaceous gland
endocrine glands
secretes hormones into interstitial fluid which then diffuse into bloodstream.
e.g pancreatic islet cells secretes insulin and glucagon into the blood
thyroid gland
connective tissue
most abundant tissue in the body
made up Extracellular matrix (very complex)
blast cell
sprout- bud ( immature cell), derived from embryonic mesoderm.
-fibroblast- fibers and ground substance
-chondroblast- cartilage
-osteoblast- bones
blast are highly mitotic (divides fast)
cyst cell
mature cells reduced mitotic activity (don't divide fast) keep matrix chondrocyte- maintains cartilage osteocyte- maintains bone
six types of connective tissue
fibroblast plasma adipocytes mast cells leukocytes macrophages
extracellular matrix conforms of
- ) fibers
2. ) ground substances
grounds substances
occupies the space btw the cell and the fibers
consistency varies
liquid- semiliquid- gelatinous to hard
blood- cartilage- bone
support and bounds cells together
provide medium for exchange of substances btw blood and tissue
ground substance components
water and other large organic mol. complex polysaccharides, etc
hyaluronic acid- binds fibers and cells together
second type of components are
fibers
collagen
reticular
mesenchyme
all connective Tx of the fetus
mucous CT only in umbilical cord (Wharton’s Jelly)
loose areolar tissue
most common of CT in body
functions- strength, elasticity and support
cell types- mast cells, fibroblast, plasma cells, macrophages
(lots of cells)
loose adipose tissue
cell type adipocyte
functions- energy storage, insolation, endocrine
loc- subcutaneous layers of skin around heart and kidneys
loose reticular tissue
main fibers- reticular
binding, scaffolding for soft tissue
locations- lymph nodes and spleen
dense regular
functions- strong attachment btw structures
loc- tendons and ligaments
main fiber is collagen- looks like sand
cell type fibroblast
dense irregular
dense collagen fibers irregularly arrange
func. strength usually forms a sheet
loc- facia, heart valves
dense elastic
fibroblast, little ground substance,
funtion- allows stretching
loc- lung tissue, hear valve, trachea, wall of arteria
cartilage
dense network of collagen and fibers embedded in rubbery ground substance
perichondrium- in almost all cartilages, member that covers dense irregular connective tissue,
hyaline cartilage perichondrium)
most abundant, end of bones, bronchi, ribs, nose, trachea, larynx, trachea tubes , and fetus skeleton
flexible, weakest form of cartilage
fibrocartilage (no perichondrium)
bundles of collagen fibers, ground substance rubbery,
cell type- chondrocyte
loc- knee caps, invertebrates disc.
functions- strongest form of cartilage- support
elastic cartilage ( perichondrium)
flexibles support shape
cartilage of ear
chondrocyte, rubbery ground substance, bundles of elastic fibers
osseous tissue
main fibers- collagen ground substance- minerals, calcium carbonate, calcium phosphate. osteocytes formed from osteoblast support protection and shape loc- skeleton parece girasol
liquid CT ( blood and lymph)
main fibers are not present in circulating blood but forms blood clots
liquid matrix
blood cells- erythrocytes, leukocytes and platelets
lymph- similar to plasma but less protein
membranes
flat sheets of pliable tissue 1.) epithelium serous mucus cutaneous 2.) synovial
mucous membrane
lining cavities that opens to the outside- produce mucus- goblet cells. connective tissue is lamina propia
muscle tissue
skeletal, smooth, myocardial.
nervous tissue
neurons and neuroglia
