overiew of GI

Question 1

What type of cells handle digestion?

Answer 1

exocrine epithelial

smooth muscle

Question 2

what type of cells handle absorption?

Answer 2

absorptive epithelial

Question 3

True or False. . Taste buds can distinguish 12 different tastes.

Answer 3

False. 6

Question 4

Salivary glands secrete what exocrine enzyme?

Answer 4

amylase

Question 5

Which third of the esophagus is responsible for peristaltic contractions?

Answer 5

lower 2/3 (smooth muscle)

Question 6

a patient presents with heartburn and sour taste in mouth when lying down, what could possibly be causing this?

Answer 6

GERD. LES (lower esophageal sphincter fails to fully close)

Question 7

What is are 2 substance important for protein digestion?

Answer 7

pepsin (from chief cells)

HCl (parietel epitheleal cells)

Question 8

What is gastric lipase?

Answer 8

secreted by fundic chief cells continues lipid digestion initiated by lingual lipase

Question 9

True or False. Dietary nutrients are absorbed in the stomach?

Answer 9

False. NO mucosal absorptive cells of small intestines

Question 10

what is the longest part of small intestine?

Answer 10

ileum - 14 feet

Question 11

What is the only steroid associated with GI degestion that is secreted via the endocrine system?

Answer 11

aldosterone (from adrenal cortex)

Question 12

True or False: Parasympathetic extrinsic fibers largely DEPRESSES GI secretion and motility

Answer 12

False: EHANCES

Question 13

True for False. Somatic Nervous System fibers do NOT have ganglion.

Answer 13

True

Question 14

The following enzymes hyrolyze what?
lipases
disaccharidases
proteases

Answer 14

lipase — fat to monoglycerides and fatty acid
disaccharidases – Carbs to monosacharides
poteases — PRO to amino acids and small peptides

Question 15

why is there no gut transport maxium?

Answer 15

a) there is excess transport capacity (small intestine ~ 20 ft long), and
b) flow through the GI tract is regulated by regulation of stomach and
small intestinal motility to promote absorption of the entire meal.

Question 16

True or false. The GI tract IS involved in the homeostatic regulation of most blood plasma constituents

Answer 16

False. IS NOT

Question 17

All of the following are exocrine glands:

Answer 17

salivary glands
gastric glands
pancreas
liver
small intestine

Question 18

What is the shape of the glands in the pancrease and salivary glands?

Answer 18

acinar (grape cluster like)

Question 19

What ion provides energy for Na (and thus H20) to enter the small intestinal lumina?

Answer 19

Cl- (negative ion) via chloride chanel on the lumen side of membrane

Question 20

True of False. LARGE differences in osmolarity between the lumen and the blood of GI epithelial tissues can bring about large absorptive or secretory fluxes of water

Answer 20

False: SMALL

Question 21

What is the average aborption of american adult?

Answer 21

net absorption = 1100 ml

Question 22

How does cholera toxin promote increase Na and H2O movement into small intestines lumina?

Answer 22

opens Cl- chanels via increase in cAMP thus increase flow of Cl -