Carbohydrates Biochemistry Set 5

/31

Biochemistry (Carbohydrates And Carbohydrate Metabolism Set 5)

MCQ

1 / 31

1. The glycolysis is regulated by

A) Pyruvate kinase

B) Hexokinase

C) Phosphofructokinase

D) All of these

2 / 31

2. Phenylalanine is the precursor of

A) L-DOPA

B) Tyrosine

C) Throxine

D) Histamine

3 / 31

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

A) ITP only

B) GTP (or) ITP

C) None of these

D) GTP only

4 / 31

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

A) 2

B) 6

C) 4

D) 8

5 / 31

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

A) An increased conversion of pyruvate to lactate

B) A decreased NADH/NAD+ ratio

C) Decreased oxidation of pyruvate of CO2 and water

D) Decreased concentration of AMP

6 / 31

6. 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) Succinylcat→ Succinic acid

D) Citric acid→ Isocitric acid

7 / 31

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

A) Uncouplers

B) All of these

C) Electrons

D) Protons

8 / 31

8. The synthesis of glucose from pyruvate
by gluconeogenesis

A) Requires oxidation/reduction of FAD

B) Is inhibited by elevated level of insulin

C) Requires the participation of biotin

D) Occurs exclusively in the cytosol

9 / 31

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

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

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

C) Hemolytic anemia

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

10 / 31

10. 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) Pyruvate kinase catalyses an irreversible reaction

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

11 / 31

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

A) Glycerol

B) α-ketoglutarate

C) Lactate

D) Acetyl CoA

12 / 31

12. The reaction catalysed by phosphofructokinase

A) Uses fruitose-1-phosphate as substrate

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

C) Is inhibited by fructose 2, 6-bisphosphate

D) Is activated by high concentrations of ATP and citrate

13 / 31

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

A) 1

B) 4

C) 6

D) 2

14 / 31

14. The reaction catalysed by phosphofructokinase

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

B) Is activated by high concentrations of ATP and citrate

C) Is inhibited by fructose 2, 6-bisphosphate

D) Uses fruitose-1-phosphate as substrate

15 / 31

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

A) Malate dehydrogenase

B) Isocitrate dehydrogenase

C) Fumarase

D) Aconitase

16 / 31

16. An uncoupler of oxidative phosphorylation such as dinitropheno

A) Inhibits electron transport without impairment of ATP synthesis

B) Allow electron transport to proceed without ATP synthesis

C) Inhibits electron transport and ATP synthesis

D) Specially inhibits cytochrome b

17 / 31

17. Which of the following reactions is unique
to gluconeogenesis

A) Lactate Pyruvate

B) Phosphoenol pyruvate pyruvate

C) Glucose-6-phosphate Fructose-6-phosphate

D) Oxaloacetate phosphoenol pyruvate

18 / 31

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

A) Gain electrons

B) Lose and gain electrons

C) Lose (or) gain electrons

D) Lose electrons

19 / 31

19. The free energy change, AG

A) Is equal to zero at equilibrium

B) Is equal to –RT in keq

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

20 / 31

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

A) Produce NADH

B) Reduce oxidizing agents such as H2O2

C) Produce NADPH

D) Reduce methemoglobin to hemoglobin

21 / 31

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

A) Glucose-6-p-dehydrogenase

B) Glyceraldehyde-3-p dehydrogenase

C) Transketolase

D) Phosphogluconate dehydrogenase

22 / 31

22. Under standard conditions

A) Keq is equal to 1

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

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

23 / 31

23. Cori cycle is

A) Both (A) & (B

B) uptake of glycose

C) reuse of glucose

D) Synthesis of glucose

24 / 31

24. Glycogen is present in all body tissues
except

A) Liver

B) Kidney

C) Brain

D) Stomach

25 / 31

25. Phenylalanine is the precursor of

A) Tyrosine

B) Throxine

C) L-DOPA

D) Histamine

26 / 31

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

A) Protein

B) CO2

C) ATP, Protein and CO2

D) CO2 and ATP

27 / 31

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

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

B) It is an anaerobic process

C) It occurs in cytosol

D) It is amphibolic in nature

28 / 31

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

A) Reduce oxidizing agents such as H2O2

B) Reduce methemoglobin to hemoglobin

C) Produce NADPH

D) Produce NADH

29 / 31

29. Glucokinase

A) None of these

B) Is widely distributed and occurs in most mammalian tissues

C) Is widely distributed in Prokaryotes

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

30 / 31

30. The conversion of pyruvate to acetyl CoA
and CO2

A) Occurs in the cytosol

B) Is reversible

C) Depends on the coenzyme biotin

D) Involves the participation of lipoic acid

31 / 31

31. 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 inhibited by oligomycin

C) ) It can bind molecular O2

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

Your score is

The average score is 41%

Carbohydrates Biochemistry Set 5

Follow Us on Social Media