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This section includes 132 Mcqs, each offering curated multiple-choice questions to sharpen your Biochemistry knowledge and support exam preparation. Choose a topic below to get started.
1. |
When the amino acid alanine (R-group is CH) is added to a solution with a pH of 7.3, alanine becomes |
A. | a cation |
B. | nonpolar |
C. | a zwitterions |
D. | an isotope |
Answer» D. an isotope | |
2. |
The sulphur containing side chain of cysteine is |
A. | ampiphillic, highly reactive and capable of reacting with another cysteine |
B. | hydrophillc, highly reactive and capable of reacting with another cysteine |
C. | hydrophobic, highly reactive and capable of reacting with another cysteine |
D. | none of the above |
Answer» D. none of the above | |
3. |
The sequence of letters 'WYQN' will represent |
A. | Tryptophan, tyrosine, glutamic acid, asparagine |
B. | Tryptophan, tyrosine, glutamine, asparagine |
C. | Tryptophan, glutamine, tryptophan, asparagine |
D. | Glutamine, tyrosine, tryptophan, aspartic acid |
Answer» C. Tryptophan, glutamine, tryptophan, asparagine | |
4. |
An intermediate of the citric acid cycle that undergoes reductive amination with glutamine as nitrogen donor is |
A. | α-ketoglutarate |
B. | Glutamine |
C. | NADPH |
D. | H⁺ |
Answer» B. Glutamine | |
5. |
Phosphorylation of AMP to ADP is promoted by |
A. | Adenylate kinase |
B. | Aspartate transcarbamoylase |
C. | Dihyhroorotase |
D. | Cytidylate synthase |
Answer» B. Aspartate transcarbamoylase | |
6. |
A second amino group is transferred to cituilline from |
A. | Aspartate |
B. | Glutamate |
C. | Alanine |
D. | Guanine |
Answer» B. Glutamate | |
7. |
The cyclized derivative of glutamate is |
A. | Proline |
B. | Arginine |
C. | Glutamine |
D. | Serine |
Answer» B. Arginine | |
8. |
Which of the following produce pyruvate? |
A. | Leucine |
B. | Isoleucine |
C. | Lysine |
D. | Alanine |
Answer» E. | |
9. |
Which of the following is a non-essential amino acid? |
A. | Methionine |
B. | Threonine |
C. | Lysine |
D. | Cysteine |
Answer» E. | |
10. |
Glutamine is converted to glutamate and NH₄⁺ by |
A. | Amino transferases |
B. | Glutaminase |
C. | Glutamine synthase |
D. | Glutamate dehydrogenase |
Answer» C. Glutamine synthase | |
11. |
Nitrogen atoms of urea produced in the urea cycle are derived from |
A. | Ammonia and aspartic acid |
B. | Nitrate |
C. | Nitrite |
D. | Ammonia |
Answer» B. Nitrate | |
12. |
Pyridoxal phosphate and its aminate form, pyridoxamine phosphate are tightly bound coenzymes of |
A. | Amino transferases |
B. | Glutaminase |
C. | Glutamine synthase |
D. | Glutamate dehydrogenase |
Answer» B. Glutaminase | |
13. |
Conversion of dUMP to dTMP is catalyzed by |
A. | Thymidylate synthase |
B. | Dihydrofolate reductase |
C. | Dihyhroorotase |
D. | Cytidylate synthase |
Answer» B. Dihydrofolate reductase | |
14. |
The carbon atom source while producing urea in the urea cycle is |
A. | CO₂ |
B. | Glucose |
C. | Aspartic acid |
D. | Arginine |
Answer» B. Glucose | |
15. |
The first intermediate in cholesterol synthesis is |
A. | Mevalonate |
B. | Isoprene |
C. | Squalene |
D. | Ethylene |
Answer» B. Isoprene | |
16. |
Generally the receptors for steroid hormones reside at |
A. | Nucleoplasm |
B. | Nuclear membrane |
C. | Cytoplasm |
D. | Plasma membrane |
Answer» B. Nuclear membrane | |
17. |
Conversion of nitrogen to ammonia or nitrogenous compounds is termed as |
A. | Nitrogen fixation |
B. | Nitrification |
C. | Denitrification |
D. | Nitrogen assimilation |
Answer» B. Nitrification | |
18. |
3-phosphoglycerate is not the metabolic precursor for |
A. | Serine |
B. | Glycine |
C. | Cysteine |
D. | Arginine |
Answer» E. | |
19. |
Which of the following yield acetyl co-A via aceto-acetyl co-A? |
A. | Leucine |
B. | Isoleucine |
C. | Threonine |
D. | Alanine |
Answer» B. Isoleucine | |
20. |
Free ammonia combined with glutamate to yield glutamine by the action of |
A. | Glutaminase |
B. | Glutamine synthase |
C. | Glutamate dehydrogenase |
D. | Amino transferase |
Answer» C. Glutamate dehydrogenase | |
21. |
Lignin is derived from |
A. | Phenylalanine |
B. | Valine |
C. | Tryptophan |
D. | Arginine |
Answer» B. Valine | |
22. |
The first enzyme in the pathway carbamoyl phosphate synthase I, is allosterically activated by |
A. | N-acetylglutamate |
B. | Acetyl coA |
C. | Glutamate |
D. | Carbamoyl phosphate |
Answer» B. Acetyl coA | |
23. |
Glutamate is metabolically converted to α-ketoglutarate and NH₄⁺ by a process |
A. | Oxidative deamination |
B. | Transamination |
C. | Reductive deamination |
D. | Deamination |
Answer» B. Transamination | |
24. |
Which of the following is the integral membrane protein of smooth ER? |
A. | Thiolase |
B. | HMG co-A synthase |
C. | HMG co-A reductase |
D. | Pyruvate kinase |
Answer» D. Pyruvate kinase | |
25. |
Which of the following gives rise to methionine, threonine and lysine? |
A. | Pyruvate |
B. | Glutamate |
C. | Aspartate |
D. | Serine |
Answer» D. Serine | |
26. |
The branched chain amino acid is not |
A. | Leucine |
B. | Isoleucine |
C. | Valine |
D. | Alanine |
Answer» E. | |
27. |
The first amino group entering into urea cycle is |
A. | Carbomyl phosphate |
B. | Ornithine |
C. | Cituilline |
D. | Argininosuccinate |
Answer» B. Ornithine | |
28. |
The first step in the catabolism of most L-amino acids once they have reached the liver is promoted by |
A. | Amino transferases |
B. | Glutaminase |
C. | Glutamine synthase |
D. | Glutamate dehydrogenase |
Answer» B. Glutaminase | |
29. |
The necessary coenzyme for transamination reactions is |
A. | Pyridoxal phosphate |
B. | Thiamine pyrophosphate |
C. | NAD |
D. | Coenzyme A |
Answer» B. Thiamine pyrophosphate | |
30. |
Which of the following are exclusively glucogenic? |
A. | Arginine |
B. | Leucine |
C. | Lysine |
D. | Threonine |
Answer» B. Leucine | |
31. |
The reaction of glutamate and NH₄⁺ to yield glutamine is catalyzed by |
A. | Uridylyltransferase |
B. | Adenylyltransferase |
C. | Glutamate synthase |
D. | Glutamine synthase |
Answer» E. | |
32. |
Which of the following yield acetyl coA directly? |
A. | Phenylalanine |
B. | Isoleucine |
C. | Lysine |
D. | Alanine |
Answer» C. Lysine | |
33. |
Almost 85 % of produced millions of tones of ammonia (NH₃) is used for making |
A. | glass |
B. | fertilizers |
C. | urea |
D. | nitrogen |
Answer» C. urea | |
34. |
Steroids have ______________ |
A. | Sterol nucleus with two alkyl chain attached to the ring D of cholesterol |
B. | Sterol nucleus with two CH₃ between C and D ring and A and B ring of cholesterol |
C. | Sterol nucleus without CH₃ between C ring and D ring of cholesterol |
D. | Sterol nucleus but lack the alkyl chain attached to the ring D of cholesterol |
Answer» E. | |
35. |
Which of the following is a PLP-requiring enzyme? |
A. | Ornithine decarboxylase |
B. | Glutathione peroxidase |
C. | Glutamine synthase |
D. | Glutamate synthase |
Answer» B. Glutathione peroxidase | |
36. |
Formation of organic nitrogen compounds like amino acids from inorganic nitrogen compounds is called as |
A. | Nitrogen fixation |
B. | Nitrification |
C. | Denitrification |
D. | Nitrogen assimilation |
Answer» E. | |
37. |
How many carbons are present in geranyl pyrophosphate? |
A. | 8 |
B. | 9 |
C. | 10 |
D. | 11 |
Answer» D. 11 | |
38. |
A person suffering from phenylketonuria on consumption food containing high phenylalanine may lead to the accumulation of |
A. | phenylalanine |
B. | phenylpyruvate |
C. | tyrosine |
D. | isoleucine |
Answer» C. tyrosine | |
39. |
Transamination is the transfer of an amino |
A. | acid to a carboxylic acid plus ammonia |
B. | group from an amino acid to a keto acid |
C. | acid to a keto acid plus ammonia |
D. | group from an amino acid to a carboxylic acid |
Answer» C. acid to a keto acid plus ammonia | |
40. |
Histidine is degraded to α-ketoglutarate and is described as a |
A. | gluco amino acid |
B. | glucogenic amino acid |
C. | ketogenic amino acid |
D. | keto-gluco amino acid |
Answer» C. ketogenic amino acid | |
41. |
Which of the following is degraded to methylmalonylsemialdehyde? |
A. | Glutamine |
B. | Tyrosine |
C. | Thymine |
D. | Leucine |
Answer» D. Leucine | |
42. |
Which of the following produce oxaloacetate? |
A. | Aspartate |
B. | Isoleucine |
C. | Threonine |
D. | Alanine |
Answer» B. Isoleucine | |
43. |
Which of the following gives rise to γ-amino butyrate? |
A. | Glutamate synthase |
B. | Glutamate decarboxylation |
C. | Glutamine synthase |
D. | Pyruvate decarboxylation |
Answer» C. Glutamine synthase | |
44. |
Glutathione peroxidase contains a covalently bound |
A. | Selenium atom |
B. | Calcium atom |
C. | Magnesium atom |
D. | Copper atom |
Answer» B. Calcium atom | |
45. |
Which of the following is the precursor for auxin? |
A. | Phenylalanine |
B. | Valine |
C. | Tryptophan |
D. | Arginine |
Answer» D. Arginine | |
46. |
Which of the following is not an aromatic amino acid? |
A. | Phenylalanine |
B. | Tyrosine |
C. | Tryptophan |
D. | Leucine |
Answer» E. | |
47. |
Tyrosine gives rise to a family of catecholamines that does not include |
A. | Dopamine |
B. | Norepinephrine |
C. | Epinephrine |
D. | Cortisol |
Answer» E. | |
48. |
The reaction vessel of ammonia (NH₃) production is composed of |
A. | 400-500 temperature |
B. | 25-300 atm pressure |
C. | iron |
D. | all of above |
Answer» E. | |
49. |
Nitric acid (HNO₃) is made from |
A. | ammonium |
B. | nitrogen |
C. | nitrate |
D. | ammonia |
Answer» E. | |
50. |
In car engine, the fuel is in compressed form and ignited by |
A. | key |
B. | spark |
C. | accelerator |
D. | brake |
Answer» C. accelerator | |