Lecture 3: Histology 2 (Chamier/Baekey)

Question 1

6 surface area modifications of the small intestine

Answer 1

1. length and convolution
2. plicae circulares
3. villi and crypts
4. epithelial cells on surface of villi
5. microvilli project from epithelial cells
6. polysaccharides of membrane glycoproteins

Question 2

Which parts of the small intestine are plicated?

Answer 2

duodenum and jejunum

Question 3

which tunic layers comprise the plicae circularis?

Answer 3

tunica mucosa and tunica submucosa

Question 4

which tunic layers comprise the villi and crypts of the small intestine?

Answer 4

tunica mucosa

Question 5

what structures lie within the villi and crypts of the small intestine?

Answer 5

veins, arteries, lacteals, and lymphatics

Question 6

fx of microvilli

Answer 6

greatly increase the surface area of small intestine lining cells. Uses glycocalyx to increase adsorption of pancreatic enzymes and enhance digestion and absorption at the cell surface

Question 7

what are enterocytes?

Answer 7

lining cells of small intestine surface mucosa

Question 8

GALT =

Answer 8

gut associated lymphoid tissue. Contains migrating lymphocytes and is a major component of the immune system

Question 9

What type of cells reside in the surface mucosa of the small intestine?

Answer 9

• lining cells/enterocytes
• goblet cells
• enteroendocrine cells

Question 10

What type of cells reside in the crypts of lieberkuhn of the small intestine?

Answer 10

• lining cells
• goblet cells
• enteroendocrine cells
• paneth cells
• basal cells

Question 11

fx of paneth cells

Answer 11

are filled with granule cells that may have antimicrobial properties

Question 12

what are peyer’s patches?

Answer 12

large lymphoid aggregations in the intestine. Most prominent in the ileum. Are GALT

Question 13

T or F: paneth cells do not migrate

Answer 13

T

Question 14

T or F: small intestine has greater capacity than large intestine to repair itself

Answer 14

T

Question 15

main functions of large intestine

Answer 15

• microbial activity (mainly in the cecum)
• absorption of water, electrolytes, vitamins (mainly in the colon)
• secretion of lubricating mucus
• peristalsis

Question 16

peristalsis is important for:

Answer 16

mixing and propulsion of ingesta from the body

Question 17

surface area is increased in the large intestine via

Answer 17

longitudinal plications (small intestine uses mainly circular folds)

Question 18

T or F: small intestine has greater blood supply than large intestine

Answer 18

T

Question 19

fxs of hepatocytes

Answer 19

1) secrete bile salts/acids, excrete bile pigments
2) synthesize sugars, plasma proteins, clotting factors, lipids, urea, ketone bodies
3) store lipids, vitamins, glycogen
4) transform toxins, drugs, hormones
5) metabolize lipids, proteins, carbs

Question 20

how do bile salts travel from central vein of hepatocyte to the bile duct?

Answer 20

via bile canaliculi

Question 21

Describe the organization of hepatocytes

Answer 21

Plates of hepatocytes are arranged in radial patterns, are surrounded by interlobular connective tissue, and are separated by sinusoids.

• central vein in the center of each plate
• portal triads in the interlobular connective tissue
• 1 hepatocyte is assoc. with multiple sinusoids and canaliculi*

Question 22

what are the 3 components of a portal triad?

Answer 22

interlobular bile duct, hepatic artery, and hepatic portal v.

Question 23

importance of hepatic artery with respect to hepatic vasculature

Answer 23

• supplies O2 and metabolic substrates

- supplies 1/5 of the sinusoidal volume

Question 24

importance of hepatic portal v. with respect to hepatic vasculature

Answer 24

• brings substances from small intestine and spleen

- supplies 4/5 of the sinusoidal volume

Question 25

drainage pathway from central vein to hepatic veins

Answer 25

central v. --> sinusoids --> sublobar vv. --> hepatic vv.

Question 26

main fxs of the gallbladder

Answer 26

storage, concentration, and acidification

Question 27

type of epithelium of tunica mucosa of gall bladder

Answer 27

simple columnar

Question 28

tunica muscularis of gall bladder has smooth or striated m.?

Answer 28

smooth

Question 29

pathway of bile from bile canaliculi to duodenum or gall bladder

Answer 29

bile canaliculi --> biliary ductules --> interlobar bile ducts --> intrahepatic ducts --> hepatic ducts --> cystic ducts --> gall bladder OR bile duct --> duodenum

Question 30

cell types of the pancreas

Answer 30

- serous acinar cells - centroacinar cells - cuboidal epithelium - goblet cells

Question 31

fx of serous acinar cells in the pancreas

Answer 31

secrete zymogen granules containing enzymes that are released into the duct system

Question 32

fx of centroacinar cells in the pancreas

Answer 32

line acinus/adenomeres (collections of acinar cells that secrete into a common intralobular duct)

Question 33

fx of cuboidal epithelium in the pancreas

Answer 33

lines intralobular and interlobular secretory ducts

Question 34

fx of crop

Answer 34

An esophageal diverticulum that is used for storage of feed, and later regurgitation to young. Lies before the thoracic inlet

Question 35

what is a proventriculus?

Answer 35

a bird's "stomach." Undergoes acidic and enzymatic digestion

Question 36

the ventriculus includes what structure in birds?

Answer 36

the gizzard

Question 37

the cloaca is a common opening for:

Answer 37

- GI - urinary - genital - Bursa of Fabricius (organ involved in hematopoiesis)

Question 38

vent

Answer 38

outer opening of the cloaca

Question 39

koilin

Answer 39

a carb-protein complex that lines and protects the muscles of the gizzard

Question 40

T or F: the cecum is paired in birds

Answer 40

T