Carbohydrates Biochemistry Set 5

/31

Biochemistry (Carbohydrates And Carbohydrate Metabolism Set 5)

MCQ

1 / 31

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

A) It occurs in cytosol

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

C) It is an anaerobic process

D) It is amphibolic in nature

2 / 31

2. 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 bind molecular O2

B) It is inhibited by oligomycin

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

D) It can exhibit ATPase activity

3 / 31

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

A) 4

B) 2

C) 8

D) 6

4 / 31

4. Glucokinase

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

B) Is widely distributed and occurs in most mammalian tissues

C) Is widely distributed in Prokaryotes

D) None of these

5 / 31

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

A) Glyceraldehyde-3-p dehydrogenase

B) Glucose-6-p-dehydrogenase

C) Transketolase

D) Phosphogluconate dehydrogenase

6 / 31

6. Phenylalanine is the precursor of

A) Throxine

B) Tyrosine

C) Histamine

D) L-DOPA

7 / 31

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

A) Aconitase

B) Isocitrate dehydrogenase

C) Fumarase

D) Malate dehydrogenase

8 / 31

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

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

B) Hemolytic anemia

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

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

9 / 31

9. Phenylalanine is the precursor of

A) Throxine

B) Tyrosine

C) L-DOPA

D) Histamine

10 / 31

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

A) Lose (or) gain electrons

B) Lose electrons

C) Gain electrons

D) Lose and gain electrons

11 / 31

11. Cori cycle is

A) reuse of glucose

B) Synthesis of glucose

C) Both (A) & (B

D) uptake of glycose

12 / 31

12. Under standard conditions

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

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

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

D) Keq is equal to 1

13 / 31

13. The reaction catalysed by phosphofructokinase

A) Uses fruitose-1-phosphate as substrate

B) Is inhibited by fructose 2, 6-bisphosphate

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

D) Is activated by high concentrations of ATP and citrate

14 / 31

14. 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

15 / 31

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

A) GTP (or) ITP

B) GTP only

C) None of these

D) ITP only

16 / 31

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

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

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

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

D) Pyruvate kinase catalyses an irreversible reaction

17 / 31

17. Which of the following reactions is unique
to gluconeogenesis

A) Lactate Pyruvate

B) Phosphoenol pyruvate pyruvate

C) Oxaloacetate phosphoenol pyruvate

D) Glucose-6-phosphate Fructose-6-phosphate

18 / 31

18. The reaction catalysed by phosphofructokinase

A) Uses fruitose-1-phosphate as substrate

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

C) Is activated by high concentrations of ATP and citrate

D) Is inhibited by fructose 2, 6-bisphosphate

19 / 31

19. The synthesis of glucose from pyruvate
by gluconeogenesis

A) Occurs exclusively in the cytosol

B) Requires oxidation/reduction of FAD

C) Requires the participation of biotin

D) Is inhibited by elevated level of insulin

20 / 31

20. The conversion of pyruvate to acetyl CoA
and CO2

A) Occurs in the cytosol

B) Is reversible

C) Involves the participation of lipoic acid

D) Depends on the coenzyme biotin

21 / 31

21. The glycolysis is regulated by

A) Hexokinase

B) Pyruvate kinase

C) All of these

D) Phosphofructokinase

22 / 31

22. An uncoupler of oxidative phosphorylation such as dinitropheno

A) Inhibits electron transport and ATP synthesis

B) Allow electron transport to proceed without ATP synthesis

C) Inhibits electron transport without impairment of ATP synthesis

D) Specially inhibits cytochrome b

23 / 31

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

A) CO2

B) ATP, Protein and CO2

C) Protein

D) CO2 and ATP

24 / 31

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

A) 2

B) 1

C) 4

D) 6

25 / 31

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

A) Produce NADH

B) Produce NADPH

C) Reduce oxidizing agents such as H2O2

D) Reduce methemoglobin to hemoglobin

26 / 31

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

A) Produce NADPH

B) Reduce methemoglobin to hemoglobin

C) Produce NADH

D) Reduce oxidizing agents such as H2O2

27 / 31

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

A) α-ketoglutarate

B) Glycerol

C) Acetyl CoA

D) Lactate

28 / 31

28. Glycogen is present in all body tissues
except

A) Kidney

B) Liver

C) Brain

D) Stomach

29 / 31

29. The free energy change, AG

A) Is equal to –RT in keq

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

C) Is equal to zero at equilibrium

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

30 / 31

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

A) Decreased oxidation of pyruvate of CO2 and water

B) Decreased concentration of AMP

C) An increased conversion of pyruvate to lactate

D) A decreased NADH/NAD+ ratio

31 / 31

31. 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) Citric acid→ Isocitric acid

B) Succinic acid→ Fumarate

C) Succinylcat→ Succinic acid

D) socitrate→ Oxaloacetate

Your score is

The average score is 40%

Carbohydrates Biochemistry Set 5

Follow Us on Social Media