Biomolecules NEET PYQs (2005–2026) with Solutions

10 solved Biomolecules PYQs

Real NEET and AIPMT questions from this chapter, newest first. Try each one, then open the answer and the step-by-step explanation.

1. Question 1 (NEET 2026)

   NEET 2026EasyProteins

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

   1. AOption A: Secondary structure
   2. BOption B: Tertiary structure
   3. COption C: Primary structure
   4. DOption D: Quaternary structure

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   Correct answer: (A) Secondary structure

   Explanation

   Alpha-helix is a characteristic feature of the secondary structure of proteins formed by hydrogen bonding. Hence option (A) is correct.

2. Question 2 (NEET 2026)

   NEET 2026MediumFunctions of biomolecules and proteins

   Match List-I with List-II. List-I: A. Starch B. Antibody C. Concanavalin A D. Glut-4 List-II: I. Fights infection II. Energy storage III. Glucose transport IV. Lectin Choose the correct answer from the options given below :

   1. AOption A: A-I, B-II, C-IV, D-III
   2. BOption B: A-II, B-I, C-IV, D-III
   3. COption C: A-II, B-I, C-III, D-IV
   4. DOption D: A-I, B-II, C-III, D-IV

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   Correct answer: (B) A-II, B-I, C-IV, D-III

   Explanation

   A. Starch is a polysaccharide that acts as the store house of energy in plant tissues, so A-II. B. Antibodies are proteins that fight infectious agents, so B-I. C. Concanavalin A is listed in NCERT among secondary metabolites as a lectin, so C-IV. D. GLUT-4 is a protein that enables glucose transport into cells, so D-III. The matching A-II, B-I, C-IV, D-III is option (B).

3. Question 3 (NEET 2026)

   NEET 2026EasyChemical Composition

   Identify the correct statements about biomolecules. A. Lipids are generally water soluble. B. Proteins are polypeptides. C. Polysaccharides are long chains of sugars. D. Adenine and guanine are substituted pyrimidines. E. Almost all enzymes are proteins. Choose the correct answer from the options given below :

   1. AOption A: B, D and E only
   2. BOption B: B, C and E only
   3. COption C: A, B and C only
   4. DOption D: C, D and E only

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   Correct answer: (B) B, C and E only

   Explanation

   Proteins are polypeptides, polysaccharides are polymers of sugars, and most enzymes are proteins. Lipids are generally water insoluble, and adenine and guanine are purines, not pyrimidines.

4. Question 4 (NEET 2026)

   NEET 2026MediumProteins

   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:

   1. AOption A: C and D only
   2. BOption B: B and C only
   3. COption C: A and C only
   4. DOption D: A and B only

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   Correct answer: (C) A and C only

   Explanation

   Amino acids are substituted methanes. Valine is a neutral amino acid. Serine is a hydroxy amino acid, not aromatic, and lysine is a basic amino acid, not acidic.

5. Question 5 (NEET 2026)

   NEET 2026MediumProteins

   Match List I with List II: Choose the correct answer from the options given below :

   1. AOption A: A-III, B-IV, C-II, D-I
   2. BOption B: A-I, B-II, C-III, D-IV
   3. COption C: A-IV, B-III, C-II, D-I
   4. DOption D: A-III, B-II, C-IV, D-I

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   Correct answer: (A) A-III, B-IV, C-II, D-I

   Explanation

   Trypsin is an enzyme, morphine is an alkaloid, Concanavalin A is a lectin and collagen forms intercellular ground substance.

6. Question 6 (NEET 2026)

   NEET 2026MediumElemental composition of living matter

   Arrange the following elements in descending order of their contribution to percentage weight of the human body. (a) Oxygen (b) Carbon (c) Hydrogen (d) Nitrogen Choose the correct answer from the options given below :

   1. AOption A: (a), (b), (c), (d)
   2. BOption B: (c), (a), (b), (d)
   3. COption C: (b), (c), (d), (a)
   4. DOption D: (b), (a), (c), (d)

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   Correct answer: (A) (a), (b), (c), (d)

   Explanation

   By weight, oxygen is the most abundant element in the human body (about 65%), mainly because the body is largely water. Carbon comes next (about 18.5%), the backbone element of all biomolecules. Hydrogen follows (about 10% by weight; it is the most numerous atom but very light), and nitrogen comes after it (about 3.3%), present in proteins and nucleic acids. So the descending order is Oxygen > Carbon > Hydrogen > Nitrogen, i.e. (a), (b), (c), (d), which is option (A). Note: NCERT Class 11 (Biomolecules, Table 9.1) prints hydrogen as only 0.5% of human body weight, which would place nitrogen (3.3%) above hydrogen. The official answer key follows the standard body-composition values above (hydrogen about 10%), so the accepted answer is option (A).

7. Question 7 (NEET 2026)

   NEET 2026MediumEnzymes

   The following reaction depicts the activity of a particular class of enzymes: Identify the enzyme class 'E' from the following options:

   1. AOption A: Transferases
   2. BOption B: Isomerases
   3. COption C: Lyases
   4. DOption D: Ligases

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   Correct answer: (C) Lyases

   Explanation

   Lyases catalyse removal of groups from substrates without hydrolysis, often resulting in formation of double bonds.

8. Question 8 (NEET 2025)

   NEET 2025EasyChemical Composition

   Match List I with List II. Choose the correct answer from the options given below :

   1. AOption A: A-I, B-III, C-II, D-IV
   2. BOption B: A-IV, B-III, C-I, D-II
   3. COption C: A-II, B-III, C-I, D-IV
   4. DOption D: A-IV, B-III, C-II, D-I

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   Correct answer: (B) A-IV, B-III, C-I, D-II

   Explanation

   Vitamin B₁₂ deficiency causes pernicious anaemia, Vitamin D deficiency causes rickets, Vitamin B₂ deficiency causes cheilosis, and Vitamin B₆ deficiency can cause convulsions. Hence the correct matching is A-IV, B-III, C-I, D-II.

9. Question 9 (NEET 2025)

   NEET 2025MediumEnzymes

   Name the class of enzyme that usually catalyze the following reaction : S − G + S# → S + S# − G Where, G → a group other than hydrogen S → a substrate S# → another substrate

   1. AOption A: Hydrolase
   2. BOption B: Lyase
   3. COption C: Transferase
   4. DOption D: Ligase

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   Correct answer: (C) Transferase

   Explanation

   Transferases catalyze the transfer of a functional group from one substrate to another.

10. Question 10 (NEET 2025)

    NEET 2025EasyNucleic Acids

    Match List I with List II. Choose the option with all correct matches.

    1. AOption A: A-III, B-IV, C-II, D-I
    2. BOption B: A-III, B-II, C-IV, D-I
    3. COption C: A-III, B-II, C-I, D-IV
    4. DOption D: A-II, B-III, C-I, D-IV

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    Correct answer: (C) A-III, B-II, C-I, D-IV

    Explanation

    Adenosine is a nucleoside, adenylic acid is a nucleotide, adenine is a nitrogenous base, and alanine is an amino acid.