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Carbohydrate Metabolism: MCQ on Pentose Phosphate Pathway

Multiple choice questions on Pentose phosphate pathway

1) Which of the following step is common in the glycolysis and pentose phosphate pathway?
a) Conversion of glucose to glucose-6-P
b) Conversion of glucose-6-P to ribose-5-P
c) Conversion of glucose-6-P- to fructose-6-P
d) Conversion of glucose to glucose-1-P

2) Pentose phosphate pathway is responsible for generating NADPH (reducing equivalents in the cell) in the cell. 
Which of the following enzyme is involved in generating NADPH?
a) Glucose-6-P oxidase
b) Glucose-6-P dehydrogenase
c) Glucose-6-P reductase
d) Glucose-6-P synthetase

3) Which of the following step is the rate-limiting step of the pentose phosphate pathway?
a) Transketolase
b) Transaldolase
c) Glucose-6-P dehydrogenase
d) Phosphogluconate dehydrogenase

4) Insulin activates the pentose phosphate pathway. 
Which of the following enzyme is activated by insulin action?
a) Transketolase
b) Glucose-6-P dehydrogenase
c) Transaldolase
d) Phosphogluconate dehydrogenase

5) Which of the following enzyme is used for the diagnosis of thiamine deficiency?
a) Transketolase
b) Glucose-6-P dehydrogenase
c) Transaldolase
d) Phosphogluconate dehydrogenase

6) Glucose -6-Phosphate dehydrogenase is allosterically activated by
a) NADPH
b) NADH
c) NAD +
d) NADP +

7) Glucose-6-Phosphate dehydrogenase is allosterically inhibited by................................
a) Acetyl CoA
b) Citrate
c) Glucose
d) Fructose

8) In some individuals, ingesting fava beans leads to hemolytic anemia. 
Which of the following enzyme may be deficient in these individuals?
a) Glucose-6-P- dehydrogenase
b) Glucose-6-Phosphatase
c) Glucose -6-Phosphate Isomerase
d) Glycogen phosphorylase

9) What is the cause of hemolytic anemia in Glucose-6-phosphate deficiency?
a) Decreased ATP in erythrocytes
b) Decreased free radicals in erythrocytes
c) Increased sodium concentration in erythrocytes
d) Increased free radicals in erythrocytes

10) The glutathione cycle is the conversion of oxidized glutathione to reduced glutathione in the presence of NADPH. 
Which of the following enzyme catalyzes this reaction?
a) Glutathione peroxidase
b) Glutathione dehydrogenase
c) Glutathione reductase
d) Glutathione synthetase


Multiple Choice Question Answers:
1-a)Conversion of glucose to glucose-6-P
2-b)Glucose-6-P dehydrogenase
3-c) Glucose-6-P dehydrogenase
4-b)Glucose-6-P dehydrogenase
5-a) Transketolase
6-d) NADP +
7-b) Citrate
8-a) Glucose-6-P- dehydrogenase
9-d) Increased free radicals in erythrocytes
10-c)Glutathione reductase




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