Question

b.3 c. 3.3 d. 10 e. cannot be determined 27. Which of the following enzymes is correctly paired with an inhibitor? a. hexokinase: ATP b. phosphofructokinase-1: AMP C. pyruvate kinase: ATP . d. phosphofructokinase-2: citrate e. glyceraldehyde-3-phosphate dehydrogenase: 1,3-bisphosphoglycerate 28. The correct sequence of steps between succinyl-CoA and ATP in mammals to "preserve the energy of the thioester bond are: A. succinyl-phosphate. B. phosphohistidine. C. GTP. D. Acetyl-CoA. 2 A, B, C b. B, C, A

27 biochem

Answer 1

Ans:27) From the Given,

1) False, Hexokinase - ATP, it shows that ATP act as a inhibitor for hexokinase which is false, instead of this Glucose 6 phosphate is its inhibitor.

2)False, Phosphofructokinase -1: AMP, it shows that AMP is an inhibitor of phosphofrctokinase -1 which is false, instead a high ratio of ATP to ADP will inhibit the phosphofrctokinase -1.

3)True, Pyruvate kinase: ATP, it is true that ATP inhibit the pyruvate kinase by inhibiting both the L and the M forms of pyruvate kinase to slow glycolysis when the energy charge is high.

4)True,  Phosphofructokinase -2: Citrate, Citrate inhibits PFK-2 by enhancing the ATP level whch is responsible for the slow down of glycolysis.

5)False, Glyceraldehyde-3-phosphate dehydrogenase: 1,3 bi-phosphoglycerate , as GAPDH is actively inhibited by glucose, hence this is false.

Therefore in this question, Option 3 and 4 are correct if it is multiple answers type and option 3 is correct if single answer is valid.