BCH Finals Dump

Question 1

where does the hexokinase pathway usually occur?

Answer 1

muscles, kidney, and adipose

Question 2

what is the source of P in hexokinase reactions?

Answer 2

ATP

Question 3

describe hexokinase and its relationship with fructose

Answer 3

hexokinase:
high km
low affinity for fructose

Question 4

where does the fructokinase pathway usually occur?

Answer 4

liver and small intesitines

Question 5

differentiate aldolase a from aldolase b

Answer 5

aldolase a : glycolysis
::
aldolase b : fructokinase pathway

Question 6

what causes essential fructosuria?

Answer 6

deficient fructokinase

Question 7

deficient fructokinase?

Answer 7

essential fructosuria

Question 8

what causes fructose intolerance?

Answer 8

deficient aldolase B

Question 9

deficient aldolase B?

Answer 9

fructose intolerance

Question 10

alternate pathway for metabolizing fructose or glucose without phosphorylation

Answer 10

sorbitol or polyol pathway

Question 11

in the sorbitol pathway, what reduces glucose to sorbitol?

Answer 11

aldolase reductase

Question 12

what are the steps of the sorbitol pathway?

Answer 12

glucose > sorbitol
- via aldolase reductase
sorbitol > fructose
- via sorbitol dehydrogenase

Question 13

in the sorbitol pathway, what enzyme oxidizes sorbitol?

Answer 13

sorbitol dehydrogenase

Question 14

in what organs are sorbitol and fructose usually found?

Answer 14

peripheral nerves, lens, and renal glomeruli

Question 15

what condition causes the levels of sorbitol and fructose to spike?

Answer 15

diabetes mellitus

Question 16

enzyme(s) associated with lactose intolerance

Answer 16

B-galactosidase or lactase

Question 17

enzyme(s) associated with non-classical galactosemia

Answer 17

galactokinase

Question 18

non-classical galactosemia can inevitably lead to?

Answer 18

diabetic cataracts

Question 19

the accumulation of what substance can lead to diabetic cataracts?

Answer 19

galactitol;

due to increased galactose in the blood = deficient galactokinase

Question 20

what can be given in cases of lactose intolerance? why?

Answer 20

yogurt; lactose has already been partially hydrolyzed by B-galactosidease in the yogurt

Question 21

in what organs does gluconeogenesis typically occur?

Answer 21

liver and kidney

Question 22

what substance is important in the mechanism of pyruvate carboxylase? what is its role?

Answer 22

biotin; CO2 donor

Question 23

predominant AA transported to the liver from muscle proteolysis

Answer 23

alanine

Question 24

by what enzyme can fatty acids be converted to glucose?

Answer 24

B-oxidation of fatty acids to acetyl coa

Question 25

breaking down muscles during starvation yields what amino acid?

Answer 25

alanine

Question 26

in what organ is alanine transaminated to pyruvate?

Answer 26

liver