Amino acids and protein structure — practice questions

Question 1 · difficulty L2 · understanding

Histones are enriched with -

• A. Phenylalanine & Leucine
• B. Phenylalanine & Arginine
• C. Lysine & Arginine
• D. Leucine & Lysine

Question 2 · difficulty L3 · understanding

Alpha-helix is found in which level of protein structure?

• A. Secondary structure
• B. Tertiary structure
• C. Primary structure
• D. Quaternary structure

Question 3 · difficulty L3 · understanding

Which of the following statements are correct regarding amino acids? A. They are substituted methanes. B. Serine is an aromatic amino acid. C. Valine is a neutral amino acid. D. Lysine is an acidic amino acid. Choose the correct answer from the options given below:

• A. C and D only
• B. B and C only
• C. A and C only
• D. A and B only

Question 4 · difficulty L3 · understanding

Match List-I with List-II. List - I List - II (A) Primary structure of protein (I) Human haemoglobin (B) Secondary structure of protein (II) Disulphide bonds (C) Tertiary structure of protein (III) Polypeptide chain (D) Quanternary structure of protein (IV) Alpha helix and $$\beta$$ sheet Choose the correct answer from the options given below :

• A. A-III, B-IV, C-II, D-I
• B. A-III, B-II, C-I, D-IV
• C. A-I, B-III, C-II, D-IV
• D. A-IV, B-III, C-II, D-I

Question 5 · difficulty L3 · understanding

Match List - I with List - II List - I List - II (A) Protein (I) C=C double bonds (B) Unsaturated fatty acid (II) Phosphodiester bond (C) Nucleic acid (III) Glycosidic bonds (D) Polysaccharide (IV) Peptide bonds Choose the correct answer from the options given below :

• A. (A)-(II), (B)-(I), (C)-(IV), (D)-(III)
• B. (A)-(IV), (B)-(III), (C)-(I), (D)-(II)
• C. (A)-(IV), (B)-(I), (C)-(II), (D)-(III)
• D. (A)-(I), (B)-(IV), (C)-(III), (D)-(II)

Question 6 · difficulty L3 · understanding

Given below are two statements: Statement I: A protein is imagined as a line, the left end represented by first amino acid (C-terminal) and the right end represented by last amino acid (N-terminal). Statement II: Adult human haemoglobin, consists of 4 subunits (two subunits of $$\alpha$$ type and two subunits of $$\beta$$ type.) In the light of the above statements, choose the correct answer from the options given below:

• A. Both Statement I and Statement II are false.
• B. Statement I is true but Statement II is false.
• C. Statement I is false but Statement II is true.
• D. Both Statement I and Statement II are true.

Question 7 · difficulty L3 · understanding

Primary proteins are also called as polypeptides because :

• A. They can assume many conformations
• B. They are linear chains
• C. They are polymers of peptide monomers
• D. Successive amino acids are joined by peptide bonds

Question 8 · difficulty L3 · understanding

Given below are two statements: Statement I : Amino acids have a property of ionizable nature of $$-$$NH 2 and $$-$$COOH groups, hence have different structures at different pH. Statement-II : Amino acids can exist as Zwitterionic form at acidic and basic pH. In the light of the above statements, choose the most appropriate answer from the options given below:

• A. Statement I is incorrect but Statement II is correct
• B. Both Statement I and Statement II are correct
• C. Both Statement I and Statement II are incorrect
• D. Statement I is correct but Statement II is incorrect

Question 9 · difficulty L3 · understanding

Which one of the following is the most abundant protein in the animals?

• A. Collagen
• B. Lectin
• C. Insulin
• D. Haemoglobin

Question 10 · difficulty L3 · understanding

Match the following (a) Inhibitor of catalytic activity (i) Ricin (b) Possess peptide bonds (ii) Malonate (c) Cell wall material in fungi (iii) Chitin (d) Secondary metabolite (iv) Collagen Choose the correct option from the following

• A. (A) $$\to$$ (ii), (B) $$\to$$ (iii), (C) $$\to$$ (i), (D) $$\to$$ (iv)
• B. (A) $$\to$$ (iii), (B) $$\to$$ (i), (C) $$\to$$ (iv), (D) $$\to$$ (ii)
• C. (A) $$\to$$ (ii), (B) $$\to$$ (iv), (C) $$\to$$ (iii), (D) $$\to$$ (i)
• D. (A) $$\to$$ (iii), (B) $$\to$$ (iv), (C) $$\to$$ (i), (D) $$\to$$ (ii)