Digestive System

Question 1

name the organs in which chemical digestion of proteins occur:

Answer 1

stomach and small intestine

Question 2

name the cells which secrete pepsinogen

Answer 2

chief cells

Question 3

name the cells which secrete HCl

Answer 3

parietal cells

Question 4

list the functions of gastrin hormone

Answer 4

stimulates parietal and chief cells to release HCl and pepsinogen; contracts the lower oesophageal sphincter; increases stomach motility; relaxes pyloric sphincter

Question 5

list the organs and enzymes responsible for carbohydrate digestion:

Answer 5

mouth, salivary amylase
small intestine, pancreatic amylase and brush border enzymes (lactase, maltase, sucrase)

end product = monosaccharides (galactose, glucose, fructose)

Question 6

list the organs and enzymes responsible for protein digestion:

Answer 6

stomach, pepsin
small intestine, pancreatic enzymes (trypsin, chymotripsin) and brush border enzymes (dipeptidase, carboxypeptidase)

end product = amino acids

Question 7

list the organs and enzymes responsible for lipid digestion:

Answer 7

mouth, lingual lipase
stomach, gastric lipase
small intestine, emulsification via bile (ducted in from liver) and pancreatic lipase

end product = monoglycerides and fatty acids

Question 8

name the three phases of digestion:

Answer 8

cephalic, gastric and intestinal

Question 9

briefly describe the cephalic phase of digestion:

Answer 9

prepares the mouth and stomach for food thats about to be eaten; activated by smell, sight, thought and initial taste; stimulates salivary glands to secrete saliva; stimulates gastric glands to secrete gastric juice

Question 10

briefly describe the gastric phase of digestion:

Answer 10

begins when food enters the stomach; promotes gastric secretion and gastric motility

Question 11

briefly describe the intestinal phase of digestion:

Answer 11

begins when food enters the small intestine; slows the exit of chyme from the stomach; promotes the digestion of food in the small intestine; stimulates pancreatic juice, bile secretion and inhibits gastric juice

Question 12

name the organs in which chemical digestion of carbohydrates occur:

Answer 12

mouth and small intestine

Question 13

name the organs in which chemical digestion of lipids occur:

Answer 13

mouth, stomach and small intestine

Question 14

name the five major hormones involved in digestion:

Answer 14

gastrin, secretin, cholecytokinin, gastric inhibitory peptide and motilin

Question 15

what stimulates gastrin secretion and what is its role?

Answer 15

stimulated by food arriving in the stomach; stimulates pepsinogen and hydrochloric acid secretion

Question 16

what is the function of secretin?

Answer 16

stimulates secretion of sodium bicarbonate from the pancreas and bile from the liver

Question 17

what is the function of cholecytokinin?

Answer 17

stimulates the gallbladder to contract and the pancreas to release digestive enzymes

Question 18

what is the function of gastric inhibitory peptide?

Answer 18

decreases the stomach churning in order to slow the emptying of the stomach

Question 19

what is the function of motilin?

Answer 19

increases gastrointestinal motility and stimulates production of pepsin

Question 20

the chemical needed to activate pepsinogen to pepsin is:

Answer 20

hydrochloric acid