EPITHELIUM Flashcards
four basic types of tissue
epithelial, connective, muscular, nervous
Most organs can be divided into __________, which is composed of the cells responsible for the organ’s specialized functions
parenchyma
what is stroma?
cells of which have a supporting role in the organ; always CT except in brain and spinal cord
What are possible shapes of epithelial cells?
columnar, cuboidal, squamous; c ells size and morphology are generally dictated by their function
What is lamina propria
the connective tissue that underlies the epithelia lining the organs of the digestive, respiratory, and urinary systems
what is papillae?
area of contact between the epithelium and connective tissue maybe increased by irregularities at the interface in the form of small evaginations; occur most frequently in epithelial tissues subject to friction (skin and tongue)
what is Basal Pole/ domaine
region of the cell contacting the connective tissue
have specializations include the basal lamina, plasma membrane infoldings, and hemidesmosomes
what is Apical Pole
the opposite end of the basal pole, usually facing a space.
Rich in: ion channels, carrier proteins, glycoproteins, and hydrolytic enzymes, and aquaporins
what is lateral surfaces
regions of cuboidal or columnar cells that adjoin the neighboring cells
Basement membrane
All epithelial cells in contact with subjacent connective tissue have at their basal surfaces a specialized, feltlike sheet of extracellular material referred to as this
Basement membrane
All epithelial cells in contact with subjacent connective tissue have at their basal surfaces a specialized, feltlike sheet of extracellular material referred to as this It has two parts: basal lamina and reticular lamina
What is epitelial tissues?
Are cells which cover surfaces, line body cavities or form glands
What is connective tissue?
Cells that produe an extracellular matrix and serve to link or support other specialized tissues by forming tendons, bone or fatty tissue.
What is connective tissue?
Cells that produe an extracellular matrix and serve to link or support other specialized tissues by forming tendons, bone or fatty tissue.
reticular lamina
layer beneath the basal lamina, this one is more fibrous than basal lamina contains Type III collagen bound by anchoring fibrils of type VII collagen (produced by connective tissue)
Laminin
large glycoproteins that self assemble as a lacelike network immediately below the cells’ basal poles where they are held in place by the transmembrane integrins
The macromolecules in the basal lamina come from the _______
epithelial tissues
The molecules in the basal lamina are:
Type IV collagen laminin nodigen and perlecan
What are the functions of epithelial tissue?
Protection Transcellular transport Secretion Absoption Selective permeability Detection of sensations
Identify the type of cell in the image
Simple squamous epithelium
Identify the type of cell in the image
simple squamous epithelium
Identify the type of cell in the image
simple squamous epithelium
What are the functions of simple squamous epithelium?
- infiltration
- diffusion- lungs
- transport- cardiovascular system
- secretion
- reduction of friction - peritoneal cavity
Types of simple squamous epithelium:
endothelium
mesothelium
endocardium
type of epithelial lining found in blood and lymphatic vessels which form a semipermeable barrier between blood and lymphatic vessels. It can secrete factors for roles.
endothelium
What is mesothelium?
The mesothelium is the epithelium that lines the wall and covers the contents of the closed cavities of the body
Epithelial lining of ventricles and atria of the hear
Endocardium
Simple Epithelia
contain one cell layer; cell shape classification: squamous, cuboidal, or columnar
Stratified Squamous Nonkeratinized Epithelium
Lines wet cavities (mouth, esophagus, and vagina) where water loss is not a problem; the flattened cells of the surface layer contain much less keratin, retaining their nuclei and metabolic function
Stratified Squamous Keratinized Epithelium
- epithelium that gives more protection
- Layers of cells composing the free surface are dead, non nucleated, filled with keratin.
Ex. skin
Stratified squamous parakeratinized epithelium
Very similar to keratinized but many cells at the surface retain thei nuclei
Ex. hard palate and gingiva
Identify the type of epithelium cell in the image and its functions
Simple cuboidal epithelium
This cells present a centrally placed nucleus. They made uo ducts of many glands of the body, covering the ovary, composed many kidney tubules.
Identify the type of epithelium and describe
Stratified cuboidal epithelium
contains only two layers of cuboidal cells, lines the duct of cellsof glands
this epithelium are usually specialized for absorption, with apical cilia or microvilvi
simple columnar epithelium
identify type of epithelium and explain
Stratified columnar epithelium
Can be found in the conjunctiva lining the eyelids where is it both protective and mucus secreting. Large ducts in glands.
Identify epithelium and describe
Transitional epitehlium
Its compsed of layers of cells that are either squamous or cuboidal. Its located EXCLUSIVELY in the urinary system
The polarity of the cell are determined
by the properties of each domain (apical, basal, basolateral surface of cell) , which are determined by specific lipids and integral membrane proteins
examples of Modifications on apical surface
microvilli, stereocilia and flagella
Lateral domain or pole
Lateral side of the cell and has structures link the lindividual cells together into a functional unit
Junctional complexes
cell adhesion molecules (CAMs)
What are CAMs?
Cell adhesion molecules