Trans 2 Epithelium Flashcards
What are the characteristics of an epithelium?
- Avascular tissue
- Covers internal closed cavities and body tubes that communicate with the exterior
- lining or surface epithelium
- Self-renewing
- With functional and morphological polarity
- Can form glands
What are the functions of an epithelium
Selective barrier Absorption Secretion Protection Others (sensation, contractility, transport of nutrients and other elements, waterproofing)
Classification of epithelium based on morphological characteristics
Simple
Compound
Classifications of epithelium based on cell shape
Squamous
Cuboidal
Columnar
Type of squamous epithelium
Single later of flattened cells
Simple squamous epithelium
Function of simple squamous epithelium
exchange and barrier
The endothelium and mesothelium are examples of what kind of epithelium
Simple squamous
Type of simple epithelium in wc the height and width of the cells are almost equal
Simple cuboidal
Function of simple cuboidal cell
Secretion and absorption
The kidney tubule is an example of what epithelium
Simple cuboidal
Type of simple epithelium with the width smaller than the height of the cell
Simple columnar
What is the function of simple columnar cells
Secretion and absorption
The lining of the gallbladder is an example of what epithelium
Simple columnar
Type of epithelium consisting of a single layer which appears to be stratified due to different levels of the nuclei
Pseudostratified
Where can you find pseudostratified epithelium?
respiratory (lining of trachea, bronchi and nasal cavity)
Male reproductive tract (epididymis)
True or false
For compound epithelium, you describe the epithelium based on which type of cell is present in larger amounts
False, you described based on the MOST SUPERFICIAL layer
Several layers of flattened cells
Stratified squamous epithelium
Can be keratinized or non-keratinized
Function of keratinized stratified squamous epithelium
Waterproofing layer (skin)
Where to find non-keratinizing stratified squamous epithelium
Mucus-rich regions with glandular tissue underneath
Function of stratified squamous epithelium
Barrier and protection
Consists of 2-3 layers of cuboidal cells
Stratified cuboidal
Function of stratified cuboidal cells
barrier and conduit
The large excretory duct of salivary glands are made up of what kind of epithelium?
Stratified cuboidal
Usually consists of 2-3 layers of columnar cells
Stratified columnar cells
Function of stratified columnar cells
Barrier and conduit
The large excretory ducts of exocrine are made up of what type of compound epithelial cells?
Stratified columnar
Other name of transitional epithelium
Uroepithelium
Surface cells of transitional epithelium
Dome cells or umbrella cells
Cells in the transitional epithelium that allow changes in the volume without changes in the pressure of the organ
Dome cells / umbrella cells
Match the following (Transitional epithelium)
- Dome shaped
- Flattened
A. Contracted
B. Distended
Dome-shaped (contracted) -> flattened (distended)
Function of the uroepithelium
Barrier with a distensible property
True or false:
The height of the cells often reflects the level of secretory or absorptive activity
True
Three domains/surfaces of an epithelial cell
Apical
Lateral
Basal
What are the surface modifications of the apical part of the epithelial cell
Microvilli
Cilia
Stereocilia
What are the surface modifications in the lateral domain of the epithelial cell?
Tight junction
Intermediate junction
Desmosomes
Gap junctions
Surface modification of the basal domain
Hemidesmosomes
Functions of the apical cell
Increase the surface area for absorption
Move substances along the epithelial surface
Domain of epithelial cells that face the organs lumen and often have specialized projecting structures
Apical domain
Shortest non-motile projection, closely packed with upright array of fingerlike evaginations from the plasma membrane of the cell
Microvilli
Microvilli are composed of what kind of filaments
ACTIN filaments
Horizontal network of filaments which lies just below the base of microvilli, where the actin filaments are attached for RIGIDITY
Terminal web
Microvilli have this on their surfaces which serves as surface for adsorption and release of digestive enzymes
Glycocalyx
What are the functions of microvilli
Increases absorptive surface of a cell
Facilitates movement of materials
Motile surface modifications used to move mucus/ovum across surface (respiratory tract/oviduct)
Cilia
The cilia has a core of microtubules called what? And where is it attached?
Axoneme, attached to the basal body
How many peripheral doubles and central singlets does an axoneme have?
9 peripheral doubles, 2 central singlets (9:2)
How many peripheral doubles and central singlets does a basal body have?
9 peripheral doubles, 0 singlets (9:0)