Epithelium and Glands

Question 1

The basement membrane is made of what 3 structures?

Answer 1

reticular fibers (type III collagen), basal lamina (laminin, type IV collagen, proteoglycans), and hemidesmosomes

Question 2

What junction is underneath tight junctions? What does it use to attach? What is their purpose?

Answer 2

Zona adherens, or adherens junctions. Use actin filaments on the intracellular side. Stabilize and strengthen the tight junctions

Question 3

What do tight junctions use? Purpose?

Answer 3

Actin on intracellular side. Forces stuff to take transcellular route, instead of paracellular route.

Question 4

What are macula adherens also called? What are they under? what do they do? What do they use?

Answer 4

Desmosomes. Underneath adherens junctions. Stabilize cell to cell interaction. Use intermediate filaments on intracellular side

Question 5

What are macula communicans? How do they appear on LM?

Answer 5

Gap junctions. Appear as terminal bars on apical side of epithelium.

Question 6

What is stereocilia? Where are they found/what do they assist in?

Answer 6

Very long microvilli with a similar function. found in inner ear and assist with mechanosensation. Also found in the epidydimis.

Question 7

acinar vs. tubular?

Answer 7

acinar or alveolar means secretory unit is sac-like, or kind of circular.
Tubular means the secretory section is tube like.

Question 8

If an exocrine gland releases part of its cytoplasm, what gland is it?

Answer 8

apocrine gland

Question 9

If the entire secretory cell is released, what kind of gland is it?

Answer 9

holocrine.

Question 10

If a gland uses exocytosis, what kind of gland is it?

Answer 10

merocrine

Question 11

Breakdown of merocrine glands? How do they stain?

Answer 11

Mucous secreters- High in mucins (heavily glycosylated proteins), and stain clear.
serous secreters- stain very pink on apical end due to secretory vesicles full of non-glycosylated proteins.

Question 12

H. pylori and clostridium perfinges both do what?

Answer 12

disrupt zona occludens junctions to cause problems such as gastric ulcers or diarrhea.

Question 13

What is it called when epithelial layers transform from one type of cell to another?

Answer 13

metaplasia. not considered carcinogenic, can be removed if stimulus is removed (not considered pathology)

Question 14

Desmosomes use what attachment proteins?

Answer 14

cadherins

Question 15

Hemidesmosomes use what attachment proteins?

Answer 15

integrins

Question 16

convoluted tubules in the kidneys and pancreatic ducts are what kind of cells? What are these cells rich in?

Answer 16

simple cuboidal. rich in mitochondria

Question 17

classic example of unicellular gland? The RER in these cells localizes where? secretes what?

Answer 17

goblet cells. RER localizes to BL side. They secrete mucins.

Question 18

Once a person reaches 45, 90% of all tumors come from where?

Answer 18

epithelial orgin

Question 19

what is dysplasia?

Answer 19

change in size, shape, or organization of cells. Can be precancerous

Question 20

what is hyperplasia?

hypertrophy?

Answer 20

hyperplasia- increased number of cells

hypertrophy- increased size of cells

Question 21

what is pleomorphism?

Answer 21

many different sizes and shapes of cells

Question 22

What is anaplasia

Answer 22

A “de-differentiation” of cells, so new cells are less specific. Degree of it determines malignancy

Question 23

what is a papilloma mean?

Answer 23

benign tumor that arises from surface epithelium

Question 24

what is an adenoma?

Answer 24

a benign tumor that arises from a glandular epithelium

Question 25

adenocarcinoma?

Answer 25

carcinoma arising from glandular tissue