Exam 4 (Mucosal Barrier + Vomiting)

Question 1

Function of gastroduodenal mucosal barrier

Answer 1

protect epithelium from gastric acid

Question 2

What 3 physiological systems maintain the gastroduodenal mucosal barrier?

Answer 2

1. alkaline mucus barrier
2. high rate of mucosal blood flow
3. epithelial cell barrier, restitution and turnover

Question 3

The alkaline mucous barrier (of the gastroduodenal mucosal barrier) secretes what 2 things?

Answer 3

mucus layer + HCO3

Question 4

In the stomach, there is _____ exchanger which occurs from surface epithelium to form the alkaline mucus barrier. In the duodenum, there are _____ and ____ exchanger which uses ___ to neutralize H+.

Answer 4

Cl/HCO3
CFTR + Cl/HCO3
HCO3

Question 5

The high rate of mucosal blood flow maintains gastroduodenal mucosal barrier by removing ___ crossing tight junctions.

Answer 5

H+

Question 6

H+ ions that come through tight junctions are neutralized by ____ to maintain high rate of mucosal blood flow.

Answer 6

ECF (containing PO4 + HCO3)

Question 7

3 things that occur with the epithelial cell barrier to maintain the gastroduodenal mucosal barrier

Answer 7

1. cell + tight junctions
2. rapid cell turnover
3. restritution after damage