What does Biomolecules cover for NEET Chemistry?

10 lessons: Carbohydrates Classification, Disaccharides, DNA RNA Structure, Enzymes, Monosaccharides, Nucleic Acid Functions, Protein Denaturation, Protein Structure Levels, Proteins Amino Acids and Vitamins Classification.

How often has Biomolecules come up in NEET past papers?

Our set of verified past papers has 12 questions from this unit, from NEET 2020, 2021, 2022, 2023, 2024, 2025 and 2026. Each is answered against the official NTA key.

Is the Biomolecules material free?

Yes. All 10 lessons and 80 practice questions are free, with no login needed.

Biomolecules

10 lessons

Topic index in NCERT order

10 of 10 lessons by the NCERT chapter they teach from, in book order. The page is the first printed page of your NCERT book the lesson cites; PYQs are the past NEET questions on that topic.

Class 12 Chemistry (pre-2023 edition), Chapter 14

Carbohydrates Classificationp. 4120 PYQs
Monosaccharidesp. 4122 PYQs
Disaccharidesp. 4171 PYQ
Proteins Amino Acidsp. 4212 PYQs
Protein Structure Levelsp. 4231 PYQ
Enzymesp. 4251 PYQ
Protein Denaturationp. 4251 PYQ
Vitamins Classificationp. 4263 PYQs
DNA RNA Structurep. 4281 PYQ
Nucleic Acid Functionsp. 4280 PYQs

Carbohydrates Classification

8 MCQs1 revision cardWorked example

Easy Recall (3)Direct Application (3)Concept Trap (1)Calculation (1)

Disaccharides

8 MCQs1 PYQs2 revision cardsWorked example

Easy Recall (3)Calculation (1)Direct Application (3)Concept Trap (1)

DNA RNA Structure

8 MCQs1 PYQs2 revision cardsWorked example

Easy Recall (3)Direct Application (3)Concept Trap (1)Calculation (1)

Enzymes

8 MCQs1 PYQs1 revision cardWorked example

Easy Recall (3)Direct Application (3)Concept Trap (1)Calculation (1)

Monosaccharides

8 MCQs2 PYQs1 revision cardWorked example

Easy Recall (4)Direct Application (4)

Nucleic Acid Functions

8 MCQs1 revision cardWorked example

Easy Recall (3)Direct Application (3)Concept Trap (2)

Protein Denaturation

8 MCQs1 PYQs1 revision cardWorked example

Easy Recall (4)Direct Application (2)Concept Trap (1)Calculation (1)

Protein Structure Levels

8 MCQs1 PYQs1 revision cardWorked example

Easy Recall (3)Direct Application (3)Calculation (1)Concept Trap (1)

Proteins Amino Acids

8 MCQs2 PYQs1 revision cardWorked example

Easy Recall (3)Direct Application (3)Concept Trap (1)Calculation (1)

Vitamins Classification

8 MCQs3 PYQsWorked example

Easy Recall (3)Direct Application (3)Concept Trap (2)

Past-paper questions from this unit

12 questions from NEET 2020, 2021, 2022, 2023, 2024, 2025, 2026. Answers verified against NTA official keys.

By year in our set: 2020 (2) · 2021 (1) · 2022 (1) · 2023 (1) · 2024 (1) · 2025 (2) · 2026 (4)

Lesson: Protein Structure Levels

NEET 2026

The correct statement about peptides and proteins is

1Tertiary structure of proteins has two or more polypeptide subunits.

2Only the proteins having a quaternary structure are biologically active.

3In β-pleated sheet structures, peptide chains are held together by intermolecular hydrogen bonds.

4In α-helices, the polypeptide chain is twisted into a left-handed screw (helix) through intramolecular hydrogen bonds.

NTA Answer: Option 3(final)

Report an error · Every fix is public: corrections log

Lesson: Proteins Amino Acids

NEET 2026

The amino acid that gives a red-blood colour on treating its sodium fusion extract with sodium nitroprusside is

1leucine

2threonine

3methionine

4serine

NTA Answer: Option 3(final)

Report an error · Every fix is public: corrections log

Lesson: Protein Denaturation

NEET 2026

A protein undergoes reversible thermal denaturation from its initial state N to denatured state D according to N ⇌ D. At 60 °C, the concentrations of both N and D are equal at equilibrium, and the standard enthalpy change of denaturation is 666 kJ mol⁻¹. The standard entropy change (ΔS° in kJ K⁻¹mol⁻¹) of the protein upon denaturation at 60 °C is closest to

12.0

22000.0

3333.0

411.1

NTA Answer: Option 1(final)

Report an error · Every fix is public: corrections log

Lesson: Vitamins Classification

NEET 2026

Match the vitamins in List-I with their sources in List-II. List-I : A. vitamin A, B. vitamin B₁₂, C. vitamin E, D. vitamin K. List-II : I. meat, II. sunflower oil, III. green leafy vegetables, IV. carrots. Choose the correct answer from the options given below.

1A-II, B-III, C-IV, D-I

2A-IV, B-I, C-II, D-III

3A-IV, B-II, C-I, D-III

4A-III, B-I, C-IV, D-II

NTA Answer: Option 2(final)

Report an error · Every fix is public: corrections log

Lesson: Vitamins Classification

NEET 2025

Match List-I with List-II. List-I (Name of Vitamin) List-II (Deficiency disease) A. Vitamin B12 I. Cheilosis B. Vitamin D II. Convulsions C. Vitamin B2 III. Rickets D. Vitamin B6 IV. Pernicious anaemia Choose the correct answer from the options given below:

1A-IV, B-III, C-II, D-I

2A-I, B-III, C-II, D-IV

3A-IV, B-III, C-I, D-II

4A-II, B-III, C-I, D-IV

NTA Answer: Option 3(final)

Report an error · Every fix is public: corrections log

Lesson: Monosaccharides

NEET 2025

Sugar 'X' A. is found in honey B. is a keto sugar C. exists in α and β – anomeric forms. D. Is laevorotatory. 'X' is :

1Sucrose

2D-Glucose

3D-Fructose

4Maltose

NTA Answer: Option 3(final)

Report an error · Every fix is public: corrections log

Lesson: Monosaccharides

NEET 2024Revised key

The reagents with which glucose does not react to give the corresponding tests/products are A. Tollen’s reagent B. Schiff’s reagent C. HCN D. NH OH 2 E. NaHSO 3 Choose the correct options from the given below:

1B and C

2A and D

3B and E

4E and D

NTA Answer: Option 3(revised_final)

Report an error · Every fix is public: corrections log

Lesson: DNA RNA Structure

NEET 2023

Given below are two statements : Statement I : A unit formed by the attachment of a base to 1′ position of sugar is known as nucleoside. Statement II : When nucleoside is linked to phosphorous acid at 5′-position of sugar moiety, we get nucleotide. In the light of the above statements, choose the correct answer from the options given below :

1Both Statement I and Statement II are false

2Statement I is true but Statement II is false

3Statement I is false but Statement II is true

4Both Statement I and Statement II are true

NTA Answer: Option 2(final)

Report an error · Every fix is public: corrections log

Lesson: Enzymes

NEET 2022

The incorrect statement regarding enzymes is

1Enzymes are very specific for a particular reaction and substrate.

2Enzymes are biocatalysts.

3Like chemical catalysts enzymes reduce the activation energy of bio processes.

4Enzymes are polysaccharides.

NTA Answer: Option 4(final)

Report an error · Every fix is public: corrections log

Lesson: Vitamins Classification

NEET 2021

The RBC efficiency is deficiency disease of :

1Vitamin B 2

2Vitamin B 12

3Vitamin B 6

4Vitamin B 1

NTA Answer: Option 2(final)

Report an error · Every fix is public: corrections log

Lesson: Disaccharides

NEET 2020

Sucrose on hydrolysis gives :

1α-D-Fructose+β-D-Fructose

2β-D-Glucose+α-D-Fructose

3α-D-Glucose+β-D-Glucose

4α-D-Glucose+β-D-Fructose

NTA Answer: Option 4(final)

Report an error · Every fix is public: corrections log

Lesson: Proteins Amino Acids

NEET 2020

Which of the following is a basic amino acid ?

1Lysine

2Serine

3Alanine

4Tyrosine

NTA Answer: Option 1(final)

Report an error · Every fix is public: corrections log

Exam traps and common mistakes in this unit

Lesson: DNA RNA Structure

Trap

DNA vs RNA base pairing

Category: Similar Terms

Student writes A=U for DNA or A=T for RNA. DNA: A=T, G≡C. RNA: A=U (no T), G≡C.

When it triggers

Question on base pairing or sugar identity.

How to avoid

DNA: deoxyribose, A-T-G-C bases. RNA: ribose, A-U-G-C bases (uracil instead of thymine). H-bond pairs: A=T (DNA) or A=U (RNA), G≡C (3 H-bonds, both).

Lesson: Protein Denaturation

Trap

Denaturation does NOT break primary structure

Category: Similar Terms

Student claims denaturation breaks peptide bonds. Denaturation only breaks H-bonds, ionic, hydrophobic interactions; primary structure (peptide bonds) intact.

When it triggers

Question about protein denaturation effects.

How to avoid

Denaturation: heat/pH/organic solvents disrupt secondary, tertiary, quaternary structure. Primary structure (covalent peptide bonds) requires hydrolysis to break.

Lesson: DNA RNA Structure

Mistake

Writes A=U for DNA or A=T for RNA.

Root cause: concept gap

Correction

DNA: deoxyribose, A=T, G≡C. RNA: ribose, A=U (no T), G≡C.

Lesson: Protein Denaturation

Mistake

Claims denaturation breaks peptide bonds (primary structure).

Root cause: concept gap

Correction

Denaturation breaks H-bonds, ionic, hydrophobic; preserves peptide bonds. Hydrolysis (acid/base/enzyme) breaks primary structure.

Formulas in this unit

Unit-wide

DNA hydrogen bonds per base pair

A - T : 2; G - C : 3

Used to compute total H-bonds in a duplex of given GC%/AT% composition.

Symbol	Quantity	SI Unit
%GC	GC content	-

Valid when

Watson–Crick double helix

Unit-wide

General formula of monosaccharides

C_{n} (H_{2} O)_{n}

Empirical formula of simple monosaccharides; glucose/fructose are C6H12O6.

Symbol	Quantity	SI Unit
n	carbon count	-

Valid when

Open-chain or cyclic forms of aldoses/ketoses

Unit-wide

Peptide bonds in a polypeptide of N residues

# bonds = N - 1

Number of amide (peptide) bonds in a linear polypeptide of N amino acids.

Symbol	Quantity	SI Unit
N	residue count	-

Valid when

Linear (non-cyclic) polypeptide

NEET question patterns in this unit

Lesson: Carbohydrates Classification

Biomolecules — recall and classify carbohydrates, proteins, nucleic acids, vitamins; identify base pairs and peptide bonds.

RecallMedium

Common distractors

swapped classes

Tempts surface-level recall.

Questions about this unit

What does Biomolecules cover for NEET Chemistry?: 10 lessons: Carbohydrates Classification, Disaccharides, DNA RNA Structure, Enzymes, Monosaccharides, Nucleic Acid Functions, Protein Denaturation, Protein Structure Levels, Proteins Amino Acids and Vitamins Classification.
How often has Biomolecules come up in NEET past papers?: Our set of verified past papers has 12 questions from this unit, from NEET 2020, 2021, 2022, 2023, 2024, 2025 and 2026. Each is answered against the official NTA key.
Is the Biomolecules material free?: Yes. All 10 lessons and 80 practice questions are free, with no login needed.