1. All proteins contain the
(A) Same 20 amino acids
(B) Different amino acids
(C) 300 Amino acids occurring in nature
(D) Only a few amino acids
2. Proteins contain
(A) Only L- α - amino acids
(B) Only D-amino acids
(C) DL-Amino acids
(D) Both (A) and (B)
3. The optically inactive amino acid is
| (A) Glycine (C) Threonine | (B) Serine (D) Valine |
(A) Dipolar ions
(B) Nonpolar molecules
(C) Positive and monovalent
(D) Hydrophobic
5. The true statement about solutions of amino acids at physiological pH is
(A) All amino acids contain both positive and negative charges
(B) All amino acids contain positively charged side chains
(C) Some amino acids contain only positive charge
(D) All amino acids contain negatively charged side chains
6. pH (isoelectric pH) of alanine is
| (A) 6.02 (C) 6.8 | (B) 6.6 (D) 7.2 |
| 7. Since the pK values for aspartic acid are 2.0, 3.9 and 10.0, it follows that the | |
| isoelectric (pH) is (A) 3.0 | (B) 3.9 |
| (C) 5.9 | (D) 6.0 |
| 8. Sulphur containing amino acid is | |
| (A) Methionine (C) Valine | (B) Leucine (D) Asparagine |
(A) 2-Amino-3-mercaptopropanoic acid
(B) 2-Amino-3-methylbutanoic acid
(C) 2-Amino-3-hydroxypropanoic acid
(D) Amino acetic acid
10. All the following are sulphur containing amino acids found in proteins except
| (A) Cysteine (C) Methionine | (B) Cystine (D) Threonine |
| 11. An aromatic amino acid is | |
| (A) Lysine (C) Taurine | (B) Tyrosine (D) Arginine |
| (A) Osmosis (C) Immunity | (B) Transport (D) both (A )and (B) |
(A) 2-Amino 5-guanidovaleric acid
(B) 2-Pyrrolidine carboxylic acid
(C) 2-Amino 3-mercaptopropanoic acid
(D) 2-Amino propanoic acid
14. An example of α-amino acid not present in proteins but essential in mammalian metabolism is
(A) 3-Amino 3-hydroxypropanoic acid
(B) 2-Amino 3-hydroxybutanoic acid
(C) 2-Amino 4-mercaptobutanoic acid
(D) 2-Amino 3-mercaptopropanoic acid
15. An essential amino acid in man is
| (A) Aspartate (C) Methionine | (B) Tyrosine (D) Serine |
(A) Are not components of tissue proteins
(B) May be synthesized in the body from essential amino acids
(C) Have no role in the metabolism
(D) May be synthesized in the body in diseased states
17. Which one of the following is semiessential amino acid for humans?
| (A) Valine (C) Lysine | (B) Arginine (D) Tyrosine |
| 18. An example of polar amino acid is | |
| (A) Alanine (C) Arginine | (B) Leucine (D) Valine |
| (A) Serine (C) Asparagine | (B) Valine (D) Threonine |
| 20. A ketogenic amino acid is | |
| (A) Valine (C) Leucine | (B) Cysteine (D) Threonine |
| (A) Valine (C) Tyrosine | (B) Proline (D) Tryptophan |
| 22. An amino acid not found in proteins is | |
| (A) β-Alanine (C) Lysine | (B) Proline (D) Histidine |
| (A) Methionine (C) Tryptophan | (B) Glycine (D) Phenylalanine |
| 24. A vasodilating compound is produced by the decarboxylation of the amino acid: | |
| (A) Arginine (C) Glutamine | (B) Aspartic acid (D) Histidine |
(A) –CONH-linkages (B) –CSNH2 group
(C) –(NH)NH2 group (D) All of these
26. Sakaguchi’s reaction is specific for
| (A) Tyrosine (C) Arginine | (B) Proline (D) Cysteine |
| 27. Million-Nasse’s reaction is specific for the | |
| amino acid: (A) Tryptophan (C) Phenylalanine | (B) Tyrosine (D) Arginine |
| (A) Peptide bond (C) Serotonin | (B) α -Amino acids (D) Histamine |
| 29. The most of the ultraviolet absorption of proteins above 240 nm is due to their | |
| content of (A) Tryptophan (C) Glutamate | (B) Aspartate (D) Alanine |
| (A) Anserine (C) Glucagon | (B) Glutathione (D) β -Lipoprotein |
| 31. Which of the following is a tripeptide? | |
| (A) Anserine (C) Glutathione | (B) Oxytocin (D) Kallidin |
32. A peptide which acts as potent smooth muscle hypotensive agent is
| (A) Glutathione (C) Tryocidine | (B) Bradykinin (D) Gramicidin-s |
| 33. A tripeptide functioning as an important reducing agent in the tissues is | |
| (A) Bradykinin (C) Tyrocidin | (B) Kallidin (D) Glutathione |
| (A) Casein (C) Gelatin | (B) Ceruloplasmin (D) Salmine |
| 35. Carbonic anhydrase is an example of | |
| (A) Lipoprotein (C) Metalloprotein | (B) Phosphoprotein (D) Chromoprotein |
| (A) Hemoglobin (C) Nuclein | (B) Sturine (D) Gliadin |
| 37. An example of scleroprotein is | |
| (A) Zein (C) Glutenin | (B) Keratin (D) Ovoglobulin |
| (A) Nucleoprotein (C) Phosphoprotein | (B) Chromoprotein (D) Glycoprotein |
| 39. An example of phosphoprotein present | |
| in egg yolk is (A) Ovoalbumin | (B) Ovoglobulin |
| (C) Ovovitellin | (D) Avidin |
| 40. A simple protein found in the nucleopro | |
| teins of the sperm is (A) Prolamine (C) Glutelin | (B) Protamine (D) Globulin |
(A) Identical to protamine
(B) Proteins rich in lysine and arginine
(C) Proteins with high molecular weight
(D) Insoluble in water and very dilute acids
42. The protein present in hair is
| (A) Keratin (C) Myosin | (B) Elastin (D) Tropocollagen |
the protein of hair keratin takes place is
| (A) Alanine (C) Proline | (B) Methionine (D) Hydroxyproline |
| 44. In one molecule of albumin the number | |
| of amino acids is (A) 510 | (B) 590 |
| (C) 610 | (D) 650 |
| 45. Plasma proteins which contain more than 4% hexosamine are | |
| (A) Microglobulins (C) Mucoproteins | (B) Glycoproteins (D) Orosomucoids |
(A) CO2 and protons to the lungs
(B) O2 to the lungs
(C) CO2 and protons to the tissue
(D) Nutrients
47. Ehlers-Danlos syndrome characterized by hypermobile joints and skin abnormalities
is due to
(A) Abnormality in gene for procollagen
(B) Deficiency of lysyl oxidase
(C) Deficiency of prolyl hydroxylase
(D) Deficiency of lysyl hydroxylase
48. Proteins are soluble in
(A) Anhydrous acetone(B) Aqueous alcohol
(C) Anhydrous alcohol (D) Benzene
49. A cereal protein soluble in 70% alcohol but insoluble in water or salt solution is
| (A) Glutelin (C) Albumin | (B) Protamine (D) Gliadin |
| 50. Many globular proteins are stable in solution inspite they lack in (A) Disulphide bonds (B) Hydrogen bonds | |
| (C) Salt bonds | (D) Non polar bonds |
| (A) Guanidine (C) Oxalic acid | (B) Uric acid (D) Salicylic acid |
52. Globular proteins have completely folded, coiled polypeptide chain and the axial ratio (ratio of length to breadth) is
(A) Less than 10 and generally not greater than 3–4
(B) Generally 10
(C) Greater than 10 and generally 20
(D) Greater than 10
53. Fibrous proteins have axial ratio
(A) Less than 10
(B) Less than 10 and generally not greater than 3–4
(C) Generally 10
(D) Greater than 10
54. Each turn of α-helix contains the amino acid residues (number):
| (A) 3.6 (C) 4.2 | (B) 3.0 (D) 4.5 |
| 55. Distance traveled per turn of α-helix in | |
| nm is (A) 0.53 (C) 0.44 | (B) 0.54 (D) 0.48 |
| (A) 0.15 (C) 0.12 | (B) 0.10 (D) 0.20 |
| 57. The number of helices present in a collagen molecule is | |
| (A) 1 (C) 3 | (B) 2 (D) 4 |
(A) Primary structure (B) Secondary structure
(C) Tertiary structure (D) Quaternary structure
59. The a-helix of proteins is
(A) A pleated structure
(B) Made periodic by disulphide bridges
(C) A non-periodic structure
(D) Stabilised by hydrogen bonds between NH and CO groups of the main chain
60. At the lowest energy level α-helix of polypeptide chain is stabilised
(A) By hydrogen bonds formed between the H of peptide N and the carbonyl O of the residue
(B) Disulphide bonds
(C) Non polar bonds
(D) Ester bonds
Answer Key:
1. A 2. A 3. A 4. A 5. A 6. A 7. A 8. A 9. A 10. D 11. B 12. A 13.
A 14. C 15. C 16. B 17. B 18. C 19. B 20. C 21. B 22. A 23. B 24. D 25. A 26. C
27. B 28. B 29. A 30. A 31. C 32. B 33. D 34. B 35. C 36. A 37. B 38. C 39. C
40. B 41. B 42. A 43. B 44. C 45. C 46. A 47. A 48. B 49. D 50. A 51. A 52. A
53. D 54. A 55. B 56. A 57. C 58. B 59. C 60. A
0 Comments