Epithelium

Question 1

What is the difference between Parenchyma and Stroma?

Answer 1

The parenchyma contains cells responsible for the function attributed to an organ. The stroma consists of cells that have a supporting role in maintenance of the structure (and thus, function) of an organ. Stroma is always connective tissue. Parenchyma and stroma interact on a basic biological level.

Question 2

Is epithelium classified as parenchyma or stroma?

Answer 2

Parenchyma

Question 3

What is the stroma that underlies the epithelium of the respiratory, digestive, and urinary systems called?

Answer 3

Lamina Propria

Question 4

What does the basement membrane regulate?

Answer 4

-Cell adhesion -Cell polarity -Cell differentiaion -Barrier function of the epithelial layer

Question 5

What are the two layers of the basement membrane?

Answer 5

-Basal Lamina (epithelium) -Reticular Lamina (stroma)

Question 6

What are junctional complexes used for?

Answer 6

-Cell-cell adhesion -adhesion to the basal lamina -communication

Question 7

What is the purpose of tight/occluding junctions?

Answer 7

to form seals between adjacent cells

Question 8

What is the purpose of Adherent/anchoring junctions?

Answer 8

-to permit cells to adhere to one another to resist abrasion -To permit cells to anchor to the basal lamina

Question 9

What is the purpose of Gap Junctions?

Answer 9

-channels to provide communication between neighboring cells

Question 10

What is the fancy word for tight junctions?

Answer 10

Zonulae Occludens

Question 11

What two transmembrane proteins interact to form tight junctions?

Answer 11

-claudin -occludin

Question 12

What is the fancy word for Adherent junctions which form a belt-like adhesion?

Answer 12

Zonula Adherens

Question 13

What is the fancy name for adherent junctions that form a spot weld-like adhesion?

Answer 13

Maculae Adherens

Question 14

Where is the Zonula Adherens located in relation to the Zonulae Occludens?

Answer 14

It is located just below the Zonulae Occludens

Question 15

What proteins mediate the anchoring of cells together via the zona adherens?

Answer 15

-Cadherins -Catenin

Question 16

What proteins mediate the anchoring of cells together via the Maculae Adherens?

Answer 16

-Desmoglein and Desmocollin (Cadherins) -Anchor to Plakoglobin and Desmoplakin

Question 17

What do hemidesmosomes do?

Answer 17

lock down an epithelial cell to the basal lamina of the basement membrane

Question 18

What do hemidesmosomes bind to in the basal membrane?

Answer 18

-laminin -Type IV collagen

Question 19

Functions of microtubules:

Answer 19

-a component of the mitotic apparatus -important for cilia and flagella functions -important for intracellular transport of vesicles and organelles

Question 20

Functions of Microfilaments:

Answer 20

-Cellular movement -cell contractile activity -movement of vesicles (cytoplasmic streaming)

Question 21

Functions of Intermediate Filaments:

Answer 21

-More stable and intermediate in size -important for differentiated cell function and shape

Question 22

What structure directs the polymerization of microtubules?

Answer 22

Microtubule Organizing Centers (MTOCs) =Centrosomes

Question 23

Brush Border

Answer 23

Microvilli on gut epithelial cells

Question 24

What microfilament is contained in microvilli?

Answer 24

Actin

Question 25

Where are stereocilia observed?

Answer 25

The absorptive cells of The epididymis and ductus deferens-Sensory hair cells

Question 26

What is the microtubule arrangement in cilia?

Answer 26

-9:2-9 microtubule doublets and two central microtubules

Question 27

What is the 9+2 microtubule arrangement in cilia called?

Answer 27

an axoneme

Question 28

What lies at the base of cilia?What structure is it similar to?

Answer 28

-Basal body -Centriole

Question 29

What is stratified epithelium?

Answer 29

epithelium that has two or more layers of cells

Question 30

What is simple epithelium?

Answer 30

epithelium that has only one layer of cells

Question 31

What kind of cells are in thin epithelium?

Answer 31

squamous

Question 32

What kind of cells are in cube shaped epithelium?

Answer 32

cuboidal

Question 33

What type of cells are in tall epithelium?

Answer 33

columnar

Question 34

Where would I find stratified squamous keratinized epithelium?

Answer 34

Skin

Question 35

What type of epithelium permits expansion of the surface?What feature allows for this expansion?

Answer 35

-Transitional Epithelium -The presence of umbrella cells, which can stretch or distend

Question 36

What is the defining feature of Pseudostratified epithelium?Where would I find it?

Answer 36

-Tall and irregular cells which are all attached to The basement membrane. Nuclei are at different levels .-The lining of The upper respiratory tract

Question 37

What is a Merocrine gland?

Answer 37

A gland that releases product via exocytosis from membrane bound vesicles

Question 38

What is a Holocrine gland?

Answer 38

A gland that releases product when cells disrupt and lyse

Question 39

What is an Apocrine gland?

Answer 39

A gland in which the apical end of the cell partitions off and is extruded into the duct, releasing products

Question 40

What is an example of a holocrine gland?

Answer 40

Sebaceous glands

Question 41

What is an example of an apocrine gland?

Answer 41

Mammary gland

Question 42

What tissue performs merocrine secretion?

Answer 42

Pancreas Acinar Cells