Metabolic Pathways: Glycogen

Question 1

In stage 2 of catabolism, what are the small molecules from stage 1 converted into?

Answer 1

2-carbon acetyl-CoA

some ATP is produced

Question 2

What enters the Krebs cycle where it is completely degraded to CO2 and H2O?

Answer 2

acetyl group of acetyl-CoA

Question 3

Which cell types require glucose as an energy source?

Answer 3

erythrocytes
retina
renal medulla
brain

Question 4

What is the initial pathway for the conversion of glucose to pyruvate?

Answer 4

glucose + 2 ADP + 2 Pi + 2 NAD+
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2 pyruvate + 2 ATP +2 H2O + 2 NADH + 2 H+

Question 5

What does glucose turn into before eventually pyruvate?

Answer 5

• fructose-1,6-bisphosphate

- 2 triose phosphates

Question 6

In what stage of glycolysis is glucose trapped and destabilised?

Answer 6

1

Question 7

What are the two cellular needs in glycolysis?

Answer 7

production of ATP

provision of building blocks for synthetic reactions

Question 8

What are the potential control points in glycolysis?

Answer 8

Enzymes catalysing essentially irreversible reactions

Question 9

Which enzymes are responsible for the irreversible reactions in glycolysis?

Answer 9

Hexokinase
Phosphofructokinase
Pyruvate kinase

Question 10

What is the key enzyme in the control of glycolysis?

Answer 10

Phosphofructokinase

Question 11

What are the negative modulators for phosphofructokinase?

Answer 11

ATP
citrate
H+

Question 12

What are the positive modulators for phosphofructokinase?

Answer 12

AMP

fructose 2,6-bisphosphate