Epethlium tissue Flashcards
histology
study of tissues
Pathology
study of disease and injury’s
Functions of Epithelial
- Protection: microbes, heat, chemicals, dehydration, and abrasions
- Secretion: getting rid of
- adsorption: bringing something in
- Provides sensations
5 General Characteristics of Epithelial
- 3 surfaces of Epithelial tissue
- Avasuclar
- Nerve supply
- High capacity for renewal by cell division
- Consists mainly of cells bond together; little extracellular material
3 layers of Epithelial
apickle
lateral
basal surface
Apickle later
surface that is exposed to a body cavity lining of a internal organ or exterior of the body
Lateral
face adjacent cells on either side
Basal Surface
deepest later attached to the basement membrane
Basement membrane (composed of, location, function)
- composed of protein fibers
- located between the Epithelial and underlying connective tissue
- function- helps anchor Epithelial tissue to the connective tissue
Avascualr
lacks blood vessels
how does avascualr get nutrients
from blood vessels located in adjacent connective tissue by the process of diffusion
Nerve supply
will not bleed but will feel pain
High capacity for renewal by cell division
subject to a large amount of wear, tear and injury
2 types of epithelial
- covering and lining
- Glandular epithelium
what is Covering and lining classified by
- cell shape
- arrangement of cells
3 arrangement of cells
simple epithelium
pseduostartisfied epithelium
stratified epithelium
simple epithelium
single layer
Pseduostratisfied epithelium
appearing to have multiple layers of cells because the nuclei lie at different levels and not all are close to the apickle layer
stratified epithelium
2 or more layers
How is stratified epithelium named
based on the shape of the cells in the apickle layer
how many cell shapes
4
1. squamous
2. cubotial
3. columnar
4. transitional
squamous
thin, flat, and arranged like floor tiles
cubotial
as tall as they are wide
Nucleus is in the center
Columnar
Taller then they are wide
nucleus is in the middle
Transitional
cells change shape from flat to cubital
Simple Squamous epithelium
single layer of flat cells resembling a floor tile with a centrally nuclei
where is Simple Squamous epithelium found
endothelium lines the heart, blood vessels, lymphatic vessels
Function Simple Squamous epithelium
diffusion, filtration, osmosis, secretion
Mesothelium
forms the epithelium layer of the serous membrane
2 kinds of mesothlium
- peritoneum
- pericardium
simple cuboidal epithelium
single layer of cells that are as tall as they are wide with a centered located nucleus
function of simple cuboidal epithelium
secretion; absorption
where is simple cuboidal epithelium found
ovary, capscule of the lense of eyes, kidney tubules, smaller ducts of glands, secreting portion of some glands like the thyroid
Noncilliated simple columnar epithelium
cells are taller then they are wider, single layer, nucleus is near the base of the cell
2 types of Noncilliated simple columnar epithelium
- goblet cells
- absorptive cells
Goblet
secret mucas
absorptive cells
with microvilli on apickle surface
microvilli
finger like projections that increase the surface area of the plasma membrane
function of Noncilliated simple columnar epithelium
- secrets mucas
- absorbtion
where is Noncilliated simple columnar epithelium found
lines most gastrointestinal track; lot of it in small intestines, gallbladder; see it in digestive, respiratory, reproductive, urinary systems
Ciliated simple columnar
taller then wide, single layer, nucleus is at the base of cell, It has cillia on apickle layer
function of Ciliated simple columnar
moves mucus and other substances by ciliary action
where is Ciliated simple columnar found
trachea, fillopean tube, uterus, paranasal sinuses
Pseduostratisfied columnar epithelium
cells are as tall as they are wide, single layer, appears that there is more then one layer because the nuclei
where is Pseduostratisfied columnar epithelium found
trachea, epidermis (found in male), urethra
function Pseduostratisfied columnar epithelium
secrets and movement of mucas by ciliary action
Stratified epithelium
stratified names depend on the shape of the cell in the apickle layer only
stratified squamous
more than one layer, cells are flat and arranged like floor tiles in the apickle layer, the second layer is columnar
keratinized stratisfied squamous
forms superficial of the skin
Keratin
tough protein that helps protect the skin and underlying tissues from microbes, heat, and chemicals
non-keratized
lining of mouth, esophagus, vagina, epiglottis, pharynx
papsmear
check pre cancerous cells by examinary non keratized s.s.e. of vagina and cervix
where are non-keratized and Keratin
they are found where mechanical stresses are near
stratified cuboidal
Farley rare type, cells are as tall as they are wide, has at least 2 layers
where is stratified cuboidal found
sweat glands, esophageal glands, ducts of adults
function stratified cuboidal
protection and limited secretion and absorbtion
statisfied columnar
cells are taller then wide in apickle layer more then 2 layers
where is statisfied columnar found
anal mucas membrane, esophageal glands
what is the function of statisfied columnar
protection and secretion
transitional epithelium
appearence is variable cells in apickle layer range from squamous when stretched to cubotial or columnar when relaxed
Where is transitional found
urinary bladder, uritter, urethra, uterus
what is the function of transitional
distension (promits organs to stretch rupturing)
2 general characteristics of Glandular epithelium
- all glandular have a secretory
- all glands of the body or either endocrine or exocrine
Endocrine gladualr (ductless glands)
hormones= secretory product
The function of endocrine glandular
the products diffuse into blood after passing through interstitial fluid without going through a duct
Where is endocrine glandular found
thyroid, adrenal, pituitary
The function of exocrine glandular
sweat, oil, saluva, ear wax, digestive enzymes= secretory product
where is exocrine glandular found
sweat glands, oil glands, salivary glands
