amino acids

Question 1

excess AA acids catabolized to

2

Answer 1

ammonia and a keto acid

Question 2

Ammonia is excreted how?

Answer 2

urea cycle then excreted in urine

Question 3

alpha keto acid as carbon skeletons goes where

Answer 3

TCA cycle

Question 4

digestion of Amino acids begins where?

Answer 4

stomach

Question 5

digestion of amino acids in the stomach by what two things

Answer 5

acids denature proteins pepsin break bonds

Question 6

pancreatic enzymes do what to proteins? Where?

Answer 6

small intestine

degrade to small peptides and AA for absorption

Question 7

_____ cleaves trypsinogen to trypsin and trypsin cleaves and activates other______

Answer 7

endopeptidase

zymogens

Question 8

trypsin cleaves and activates other zymogens which unleashes

Answer 8

a cascade of proteolytic enzymes

Question 9

Single AA and di and tripeptides are transported intestinal cells and digested by

Answer 9

aminopeptidase

Question 10

dietary proteins are primarily used

Answer 10

synthesize new proteins

Question 11

AA acid carbon skeletons are used for what

Answer 11

TCA cycle

Question 12

What happens to amino group/ nitrogen?

Answer 12

first amino group/nitrogen is transferred from OG AA to a ketoglutarate by a transaminase with the product being glutamate,

then free ammonia liberated by glutamate dehydrogenase,

nitrogen then transported as ammonia in alanine and glutamine

to be converted to urea in the liver

urea excreted in urine by kidneys

Question 13

What are the three fates of nitrogen?

Answer 13

transamination
oxidative deamination
the urea cycle

Question 14

What has to happen to the AA acid to be catabolized?

Answer 14

remove amino/nitrogen group

Question 15

What are the two biggest AA in nitrogen catabolism

Answer 15

glutamate

alanine

Question 16

once the amino group is removed what can happen?

Answer 16

carbon skeletons can enter TCA

Question 17

Amino groups can move freely from one AA to another. What makes this magic happen?

Answer 17

transaminases

Question 18

nitrogen is transferred as an amino group from the original AA to a-ketoglutarate forming what?

Answer 18

glutamate

Question 19

name two important aminotransferases

Answer 19

ALT

AST

Question 20

glutamate dehydrogenase liberates the amino group as free _____ which leaves what?

Answer 20

a-keto acids to enter tca and ammonia for nitrogen in urea cycle