Physiology: carbohydrate & protein digestion 2

Question 1

describe the role of alpha-amylase

Answer 1

it is an endoenzyme, it breaks down polysaccharides to oligosaccharides in carbohydrate digestion

Question 2

describe the role of oligosaccharidases

Answer 2

to break down oligosaccharides to monosaccharides in carbohydrate digestion

Question 3

give 3 examples of oligosaccharidases

Answer 3

lactase, sucrase and maltase

Question 4

what are the final products of carbohydrate digestion

Answer 4

glucose, galactose and fructose

Question 5

where are the final products of carbohydrate digestion absorbed

Answer 5

in the duodenum and jejunum

Question 6

describe how they are absorbed and what mediates the absorption of glucose and galactose

Answer 6

SGLT1 mediates the secondary active transport of glucose + galactose

Question 7

describe how it is absorbed and what mediates the absorption of fructose

Answer 7

absorbed by facilitated diffusion

mediated by GLUT5

Question 8

what must proteins be digested to for efficient absorption

Answer 8

to oligopeptides and amino acids

Question 9

describe the role of HCl in protein digestion in the stomach

Answer 9

begins to denature the proteins

Question 10

describe the role of peptin in protein digestion in the stomach

Answer 10

cleaves proteins into peptides

Question 11

where are the 5 pancreatic proteases secreted from and where are they activated

Answer 11

secreted as proenzymes from acinar cells of exocrine pancreas
converted to active form in duodenum

Question 12

what 3 pancreatic proteases produce oligopeptides

Answer 12

trypsin, chymotrypsin and elastase

endopeptidases

Question 13

what 2 pancreatic proteases produce single amino acids

Answer 13

procarboxypeptidase A and B

exopeptidases

Question 14

what is an endopeptidase

Answer 14

breaks peptide bonds on non terminal amino acids

Question 15

what is an exopeptidase

Answer 15

breaks peptide bonds of terminal amino acids

Question 16

what other types of peptidases, except pancreatic, are involved in protein digestion

Answer 16

brush border peptidases and cytoplasmic peptidases

Question 17

where are amino acids absorbed

Answer 17

brush border and basolateral membrane