Tissue Organization

Question 1

Layers of tissue

Answer 1

Mucosa: Epithelium, basal lamina, reticular lamina, lamina propria (connective tissue), muscularis mucosa

Submucosa: connective tissue, Meissner’s Plexus

Muscularis propria/externa: Denser muscle,
myenteric plexus. Circular muscle more towards epithelium, longitudinal muscle on serosa side

Serosa

Question 2

Is epithelium vascularized?

Answer 2

No, gets nutrients from lumen or underlying connective tissue.
No ECM, high cellularity

Question 3

3 components of connective tissue

Answer 3

fibers, ground substance, cells

Question 4

Types of fibers

Answer 4

collagens (tensile, synthesized by fibroblasts), elastic (elasticity)

Question 5

Collagen synthesis

Answer 5

ER/Golgi
1. pro a-chain
2. hydroxylation of prolines and lysines (*Vit C)
3. Glycosylation of selected hydroxylysines
4. 3 pro-a chains wind together (procollagen)
Outside of cell:
5. propeptides cleaved –> collagen molecule
6. assembly into fibril
7. aggregation of fibrils to form fiber

Question 6

Two types of elastic fibers

Answer 6

elastin, fibrillin

Question 7

Components of ground substance

Answer 7

GAGs (i.e. HA), PGs, glycoproteins

Question 8

Bacteria and HA

Answer 8

bacteria have hyaluronidase to make ground substance more fluid to promote invasion

Question 9

simple squamous

Answer 9

endothelium, mesothelium

Question 10

simple cuboidal

Answer 10

kidney tubule

Question 11

simple columnar

Answer 11

stomach, SI

Question 12

stratified squamous keratinized

Answer 12

epidermis (prevent water loss)

Question 13

strat squamous non-keratinized

Answer 13

esophageal lining, cornea, vagina (lubrication)

Question 14

stratified cuboidal/columnar

Answer 14

rare, ducts of glands

Question 15

transitional

Answer 15

urinary tract

Question 16

pseudostratified columnar

Answer 16

respiratory tract, epididymis

Question 17

Microvilli

Answer 17

actin, increase SA for absorption

Question 18

stereocilia

Answer 18

long microvilli, actin

Question 19

cilia

Answer 19

MTs, motile

Question 20

primary cilia

Answer 20

MTs, non-motile, sensory function

Question 21

SAD PUCKER retroperitoneum

Answer 21

supra-adrenal, aorta, duodenum, pancreas, ureters, colon, kidneys, esophagus, rectum

Question 22

parenchyma

Answer 22

functional tissue of organ

Question 23

Esophagus defining features

Answer 23

• submucosal mucous glands
• submucosal lymphoid follicles
• stratified non-keratinized squamous

Question 24

stomach defining features

Answer 24

• NO glands in submucosa
• parietal (pink) and chief (purple) cells
• glandular epithelium (simple columnar)

Question 25

SI defining features

Answer 25

ALL: paneth cells (granular stains red at bottom of crypts)

Duodenum: Brunner’s glands in submucosa (big glands, for neutralizing stomach contents)
Ileum: Peyer’s Patches in submucosa (lymphoid aggregates)

Question 26

colon defining features

Answer 26

• Goblet cells scattered in epithelium, pale blue

- Paneth cells

Question 27

Pancreas defining features

Answer 27

• Acinar cells: pink centers, blue periphery

- Islet cells: pale nests