Free Classification of Proteins MCQs with Answers
62 Classification of Proteins MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Proteins are classified by composition as simple, conjugated and derived proteins, and by shape as fibrous or globular proteins. The topic relates these classes to examples such as albumin, keratin, collagen, haemoglobin and casein, while distinguishing structural proteins from proteins with transport, catalytic or regulatory roles.
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62 questions · page 2 of 4
- A. Lysine
- B. Histidine
- C. Proline
- D. Glutamic acid
Explanation: Proline is considered neither acidic nor basic because its side chain does not provide an extra strongly acidic or basic group; it has one…
Correct answer: Proline- A. Acidic character of amino acids
- B. Basic character of amino acids
- C. Dipolar character of amino acids
- D. Non-polar structure of amino acids
Explanation: An amino acid can exist as an internal salt or zwitterion, with a positively charged amino group, NH3+, and a negatively charged…
Correct answer: Dipolar character of amino acids- A. 2 amino groups and 1 carboxylic group
- B. 1 amino and 1 carboxylic groups
- C. 2 carboxylic groups and 1 amino group
- D. 2 amino and 2 carboxylic groups
Explanation: An acidic amino acid has one amino group and two carboxylic acid groups, so it has an extra carboxyl group capable of donating protons.
Correct answer: 2 carboxylic groups and 1 amino group- A. 5
- B. 10
- C. 15
- D. 20
Explanation: In the traditional school-level classification, humans require 10 essential amino acids from the diet because the body cannot synthesise…
Correct answer: 10- A. Ninhydrin test
- B. Molisch test
- C. Biuretic test
- D. Benedict test
Explanation: Ninhydrin reacts with the free amino group of most amino acids to produce a characteristic deep blue or purple colour, so it is used for…
Correct answer: Ninhydrin test- A. Carboxyl to amino group
- B. Amino to carboxyl group
- C. Amino group only
- D. Carboxyl group only
Explanation: A zwitterion forms when the acidic carboxyl group transfers its proton to the basic amino group, producing -COO- and -NH3+ in the same…
Correct answer: Carboxyl to amino group- A. Quantum structure
- B. Secondary structure
- C. Tertiary structure
- D. Primary structure
Explanation: The regular alpha-helical coiling and beta-pleated zigzag arrangement of a polypeptide are produced mainly by hydrogen bonds between…
Correct answer: Secondary structure- A. Nitrogen
- B. Amino acids
- C. Carbon and hydrogen
- D. Sulphur
Explanation: Complete hydrolysis breaks peptide bonds by reaction with water and converts a protein into its constituent amino acids.
Correct answer: Amino acids- A. Derived protein
- B. Sample protein
- C. Proteoses
- D. Conjugated protein
Explanation: A conjugated protein contains a protein part combined with a non-protein component called a prosthetic group, such as a metal…
Correct answer: Conjugated protein- A. Acidic
- B. Neutral
- C. Amphoteric
- D. Basic
Explanation: Amino acids with a greater number of NH2 groups (amine groups) are more basic because the amine groups can accept protons (H+ ions) and…
Correct answer: Basic- A. Acidic
- B. Neutral
- C. Basic
- D. Acidic and Basic
Explanation: Histidine is an amino acid that can act as both an acid and a base due to the presence of an imidazole side chain.
Correct answer: Acidic and Basic- A. i and A, ii and B, iii and C, iv and D
- B. i and B, ii and A, iii and D, iv and C
- C. i and D, ii and C, iii and B, iv and A
- D. i and C, ii and D, iii and A, iv and B
Explanation: The amino acids can be classified based on the nature of their side chains. I.
Correct answer: i and D, ii and C, iii and B, iv and A33. Antibodies are?
- A. Primary proteins
- B. Secondary proteins
- C. Tertiary proteins
- D. Quaternary proteins
Explanation: Antibodies are proteins the immune system produces to identify and neutralize foreign objects like bacteria and viruses.
Correct answer: Quaternary proteins- A. Option A
- B. Option B
- C. Option C
- D. Option D
Explanation: The primary structure of a protein is defined as the sequence of amino acids linked together to form a polypeptide chain Secondary…
Correct answer: Option D- A. Adjacent to each other
- B. In successive spiral turns
- C. Between two different polypeptide chains
- D. None of the given options
Explanation: The most common types of secondary structures are the α helix and the β pleated sheet.
Correct answer: In successive spiral turns- A. Primary structure
- B. Secondary structure
- C. Tertiary structure
- D. Quaternary structure
Explanation: Hemoglobin has a quaternary structure. It consists of two pairs of different proteins, designated the α and β chains.
Correct answer: Quaternary structure- A. Non-crystalline
- B. More amino acids
- C. Peptide bonds
- D. Soluble in aqueous medium
Explanation: The following question deals with the differences between Globular and fibrous proteins and the student must be able to identify the…
Correct answer: Soluble in aqueous medium- A. Primary Proteins
- B. Secondary Proteins
- C. Tertiary Proteins
- D. Both Primary and Tertiary Proteins
Explanation: •Primary structure of protein is the simplest level of protein structure.It comprises the number and sequence of amino acids in a protein…
Correct answer: Primary Proteins- A. Intermediate
- B. Simple
- C. Globular
- D. Fibrous
Explanation: Fibrous: This option is the correct answer. Fibrous proteins are characterized by their elongated, thread-like structure.
Correct answer: Fibrous- A. Alpha helix
- B. Beta helix
- C. Spiral
- D. Concentrate
Explanation: In protein secondary structure, the beta helix refers to a left-handed helical conformation formed by the polypeptide chain.
Correct answer: Beta helix