Carbohydrates Biochemistry Set 5

/31

Biochemistry (Carbohydrates And Carbohydrate Metabolism Set 5)

MCQ

1 / 31

1. Out of 24 mols of ATP formed in TCA cycle,
2 molecules of ATP can be formed at
“substrate level” by which of the
following reaction

A) Succinic acid→ Fumarate

B) socitrate→ Oxaloacetate

C) Citric acid→ Isocitric acid

D) Succinylcat→ Succinic acid

2 / 31

2. The reaction catalysed by phosphofructokinase

A) Is activated by high concentrations of ATP and citrate

B) Is inhibited by fructose 2, 6-bisphosphate

C) Uses fruitose-1-phosphate as substrate

D) Is the rate-limiting reaction of the glycolytic pathway

3 / 31

3. The reaction catalysed by phosphofructokinase

A) Is the rate-limiting reaction of the glycolytic pathway

B) Uses fruitose-1-phosphate as substrate

C) Is activated by high concentrations of ATP and citrate

D) Is inhibited by fructose 2, 6-bisphosphate

4 / 31

4. Glycogen is present in all body tissues
except

A) Brain

B) Stomach

C) Liver

D) Kidney

5 / 31

5. In presence of the following cofactor,
pyruvate carboxylase converts pyruvate
to oxaloacetate

A) CO2

B) Protein

C) CO2 and ATP

D) ATP, Protein and CO2

6 / 31

6. All of the following statements about the
enzymic complex that carries out the
synthesis of ATP during oxidative
phosphorylation are correct except

A) It can exhibit ATPase activity

B) It is located on the matrix side of the inner mitochondrial membrane

C) It is inhibited by oligomycin

D) ) It can bind molecular O2

7 / 31

7. Phenylalanine is the precursor of

A) Tyrosine

B) Histamine

C) Throxine

D) L-DOPA

8 / 31

8. How many ATPs are produced in the
conversion of phosphoenol pyruvate to
citrate

A) 4

B) 6

C) 1

D) 2

9 / 31

9. For conversion of oxaloacetate to
phosphoenol pyruvate, high energy
molecule is required in the form of

A) GTP (or) ITP

B) ITP only

C) None of these

D) GTP only

10 / 31

10. How many ATP molecules will be required
for conversion of 2-molecules of Lactic acid
to Glucose

A) 2

B) 8

C) 6

D) 4

11 / 31

11. The free energy change, AG

A) Is equal to –RT in keq

B) Is equal to zero at equilibrium

C) Is directly proportional to the standard free energy change, AG

D) Can only be calculated when the reactants and products are present at 1mol/1 concentrations

12 / 31

12. Which one of the following would be
expected in pyruvate kinase deficiency

A) Decreased ratio of ADP to ATP in R.B.C

B) Increased phosphorylation of Glucose to Glucose-6-phosphate

C) Increased levels of lactate in the R.B.C

D) Hemolytic anemia

13 / 31

13. Phenylalanine is the precursor of

A) L-DOPA

B) Tyrosine

C) Throxine

D) Histamine

14 / 31

14. Which one of the following statements
concerning glucose metabolism is correct

A) Pyruvate kinase catalyses an irreversible reaction

B) The conversion of Glucose to lactate occurs only in the R.B.C

C) An elevated level of insulin leads to a decreased level of fructose 2, 6-bisphosphate in hepatocyte

D) Glucose enters most cells by a mechanism in which Na+ and glucose are co-transported

15 / 31

15. Cori cycle is

A) uptake of glycose

B) reuse of glucose

C) Synthesis of glucose

D) Both (A) & (B

16 / 31

16. Which one of the following compounds
cannot give rise to the net synthesis of
Glucose

A) Acetyl CoA

B) α-ketoglutarate

C) Glycerol

D) Lactate

17 / 31

17. An allosteric enzyme responsible for
controlling the rate of T.C.A cycle is

A) Aconitase

B) Fumarase

C) Malate dehydrogenase

D) Isocitrate dehydrogenase

18 / 31

18. Electron transport and phosphorylation
can be uncoupled by compounds that
increase the permeability of the inner
mitochondrial membrane to

A) Uncouplers

B) Protons

C) All of these

D) Electrons

19 / 31

19. Which of the following statements
regarding T.C.A cycle is true

A) It is an anaerobic process

B) It contains no intermediates for GluconeogenesisIt contains no intermediates for Gluconeogenesis

C) It occurs in cytosol

D) It is amphibolic in nature

20 / 31

20. The more positive the E0, the greater the
tendency of the oxidant member of that
pair to

A) Lose and gain electrons

B) Lose electrons

C) Lose (or) gain electrons

D) Gain electrons

21 / 31

21. Reduced glutathione functions in R.B.Cs
to

A) Produce NADPH

B) Reduce oxidizing agents such as H2O2

C) Produce NADH

D) Reduce methemoglobin to hemoglobin

22 / 31

22. Compared to the resting state, vigorously
contracting muscle shows

A) A decreased NADH/NAD+ ratio

B) Decreased oxidation of pyruvate of CO2 and water

C) An increased conversion of pyruvate to lactate

D) Decreased concentration of AMP

23 / 31

23. Which of the following enzyme is not
involved in HMP shunt

A) Glyceraldehyde-3-p dehydrogenase

B) Phosphogluconate dehydrogenase

C) Glucose-6-p-dehydrogenase

D) Transketolase

24 / 31

24. Under standard conditions

A) The free energy change ∆G°, is equal to 0

B) Keq is equal to 1

C) The free energy change, ∆G°, is equal to the standard free energy change, ∆G°

D) The standard free energy change ∆G, is equal to 0

25 / 31

25. The synthesis of glucose from pyruvate
by gluconeogenesis

A) Requires the participation of biotin

B) Is inhibited by elevated level of insulin

C) Requires oxidation/reduction of FAD

D) Occurs exclusively in the cytosol

26 / 31

26. The glycolysis is regulated by

A) Pyruvate kinase

B) All of these

C) Phosphofructokinase

D) Hexokinase

27 / 31

27. An uncoupler of oxidative phosphorylation such as dinitropheno

A) Allow electron transport to proceed without ATP synthesis

B) Inhibits electron transport without impairment of ATP synthesis

C) Specially inhibits cytochrome b

D) Inhibits electron transport and ATP synthesis

28 / 31

28. Reduced glutathione functions in R.B.Cs
to

A) Reduce oxidizing agents such as H2O2

B) Produce NADH

C) Produce NADPH

D) Reduce methemoglobin to hemoglobin

29 / 31

29. Which of the following reactions is unique
to gluconeogenesis

A) Glucose-6-phosphate Fructose-6-phosphate

B) Phosphoenol pyruvate pyruvate

C) Lactate Pyruvate

D) Oxaloacetate phosphoenol pyruvate

30 / 31

30. Glucokinase

A) Is widely distributed in Prokaryotes

B) None of these

C) Is widely distributed and occurs in most mammalian tissues

D) Has a high km for glucose and hence is important in the phosphorylation of glucose primarily after ingestion of a carbohydrate rich meal

31 / 31

31. The conversion of pyruvate to acetyl CoA
and CO2

A) Is reversible

B) Involves the participation of lipoic acid

C) Depends on the coenzyme biotin

D) Occurs in the cytosol

Your score is

The average score is 40%

Carbohydrates Biochemistry Set 5

Follow Us on Social Media