3: Epithelial Border Modifications & Glands

Question 1

Epithelial junctions

Answer 1

most part of the junctional complex located on the lateral border of epithelial cells

Question 2

Tight junctions

Answer 2

outer membrane of neighboring cells is fused, sealing the intercellular space from the lumen

Question 3

3 types of cytoskeletal linked junctions

Answer 3

1. adherent junction
2. desosomes
3. hemidesmosomes

Question 4

Adherent junction

Answer 4

forms an adhesion belt near apical surface beneath tight junction, membranes not totally fused but plasma proteins (anchored by actin filaments) interact with each other

Question 5

Cadherins

Answer 5

the plasma proteins in adherent junctions

Question 6

Terminal bar

Answer 6

tight junction and adherent junction

Question 7

Desmosomes

Answer 7

similar to adherent junction but not located near the lateral luminal surface and have extracellular filaments which further anchor the membranes together

Question 8

What cell types are desmosomes common in?

Answer 8

stratified squamous

Question 9

Hemidesmosome

Answer 9

half a desmosome used to anchor the cell to the basal lamina

Question 10

Gap juctions

Answer 10

proteins form a central pore between membranes to allow of electrical and chemical communication

Question 11

What are microvilli composed of?

Answer 11

actin filaments

Question 12

Microvilli purpose

Answer 12

increase surface area in absorptive epithelia

Question 13

Striated border

Answer 13

microvilli in the gut

Question 14

Brush border

Answer 14

microvilli in renal tubules

Question 15

Stereocilia

Answer 15

branched microvilli found in the epididymis

Question 16

What cell type are microvilli commonly found on?

Answer 16

simple columnar

Question 17

What are cilia composed of?

Answer 17

microtubules

Question 18

T/F: Cilia use ATP

Answer 18

T

Question 19

What tracts are cilia commonly found in?

Answer 19

respiratory and reproductive

Question 20

What cell types are cilia usually found on?

Answer 20

pseudostratified columnar

Question 21

Glands

Answer 21

specialized epithelial cells modified into secretory structures that produce a variety of products for extracellular use

Question 22

Unicellular glands

Answer 22

single secretory cell

Question 23

What is the most common unicellular gland?

Answer 23

goblet cells

Question 24

Where are goblet cells commonly found?

Answer 24

respiratory and GI tracts

Question 25

What do goblet cells secrete?

Answer 25

mucopolysaccharides

Question 26

Multicellular glands

Answer 26

an accumulation of specialized secretory cells

Question 27

Endocrine glands

Answer 27

ductless glands that have lost their original embryonic connections to the epithelial surface form which they originated

Question 28

T/F: Endocrine glands have junctions and polarity

Answer 28

T

Question 29

Exocrine glands

Answer 29

maintain a communication (duct) within the surface epithelium

Question 30

Simple exocrine glands

Answer 30

ducts do not branch

Question 31

Adenomeres

Answer 31

secretory end pieces of simple exocrine glands

Question 32

How are simple exocrine glands classified?

Answer 32

tubular, coiled, or acinar

Question 33

Where are simple exocrine glands usually found?

Answer 33

within an organ

Question 34

Compound exocrine glands

Answer 34

have elaborate branching duct systems

Question 35

How are compound exocrine glands classified?

Answer 35

tubular, acinar, or tubuloalveolar

Question 36

Where are compound exocrine glands found?

Answer 36

they are discrete anatomic structures or organs themselves

Question 37

4 types of secretion

Answer 37

1. serous 2. mucous 3. mixed 4. lipid

Question 38

Serous secretion

Answer 38

water secretion with rounded nuclei near base of the cell and secretory granules at the apex

Question 39

Mucous secretion

Answer 39

viscous secretion of polysaccharides where the nuclei are flattened near the base and the cytoplasm is pale-stained

Question 40

Mixed secretion

Answer 40

a combination of both serous and mucous secretory units found in the same gland

Question 41

Lipid secretion

Answer 41

lipid secretion such as milk, sebum, cerumen

Question 43

What is the most common mode of secretion?

Answer 43

merocrine

Question 44

Merocrine

Answer 44

loss of secretory product only by exocytosis