Digestive System - Part I

Question 1

3 basic functions of the GI tract

Answer 1

movement of food
secretion of digestive juices
absorption of digested foods, water and electrolytes

Question 2

where are villi located?

Answer 2

small intestine

Question 3

general structure (layers) of the digestive tract (small intestine)

Answer 3

epithelium
lamina propria
submucosa
muscularis externa
serosa

Question 4

the lip has _____ epithelium

Answer 4

stratified squamous

Question 5

serous gland secretions contain a ______ that prevents the formation of a hydrophobic film on taste buds that would hinder taste ability.

Answer 5

lipase

Question 6

muscularis external of the upper esophagus is composed mostly of _________, whereas lower esophagus is mostly composed of _______

Answer 6

skeletal muscle

smooth muscle

Question 7

cardio-esophageal junction: luminal epithelium changes from _____ to ______

Answer 7

stratified squamous to simple columnar epithelium

Question 8

______ cells have granules on opposite end than lumen, because they secrete into the lamina propria.

Answer 8

argentaffin cells

Question 9

Define the protective bicarbonate flux

Answer 9

the bicarbonate from carbonic anhydrase rxn in parietal cells enters the fenestrated capillaries going just beneath the luminal surface epithelium of the stomach to neutralize the luminal acid digestion of surface cells.

Question 10

parietal cells produce: ____, _____, ____

Answer 10

HCl, bicarbonate, and intrinsic factors (vitamin b12 absorption by the gut, needed for RBC formation)

Question 11

what is the relationship between parietal cells and anemia?

Answer 11

Gastric atrophy may result in the loss of parietal cells. Parietal cells secrete intrinsic factors which are important for the absorption of vit. b12 and RBC formation. Low vitamin b12 levels can reduce proliferation of erythroblasts, producing anemia.

Question 12

enteroendocrine cells also called ______

Answer 12

Argentaffin cells