NEET 2027
HIGH-WEIGHTAGE BIOLOGY
PART 4
BIOMOLECULES • STRUCTURAL ORGANISATION DIVERSITY • HEALTH • EVOLUTION •
FOOD PRODUCTION
140 Practice Questions with Full Explanations
Simple Language • Concept + Practice Practice
Inside This Book
✓ Clear short theory for every major topic
✓ 140 carefully chosen practice questions
✓ Detailed reason why the correct option is right
✓ Detailed reason why each wrong option is wrong
✓ Written in easy Class 8–9 level English
✓ Completes the high-weightage Biology series for NEET 2027
Topics: Biomolecules • Tissues & Anatomy • Plant & Animal Kingdom
Human Health & Diseases • Evolution • Food Production Strategies
, CONTENTS
1. Biomolecules — Theory + Q1 to Q25
2. Structural Organisation (Tissues, Morphology, Anatomy) — Theory + Q26 to Q50
3. Diversity of Living Organisms (Plant & Animal Kingdom) — Theory + Q51 to Q75
4. Human Health and Diseases + Microbes — Theory + Q76 to Q100
5. Evolution — Theory + Q101 to Q120
6. Strategies for Enhancement in Food Production — Theory + Q121 to Q140
Quick Revision Tips — Last page
How to Use This Book
1. First read the short theory of the topic carefully.
2. Then solve the questions of that topic.
3. Read why the correct answer is right and why the other options are wrong.
4. This builds real understanding and helps you avoid common mistakes in NEET.
NEET 2027 | High-Weightage Biology | Part 4 – Biomolecules to Evolution Page 2
, 1. BIOMOLECULES
Biomolecules are organic compounds present in living organisms. Major classes: Carbohydrates, Proteins, Lipids,
Nucleic acids. Carbohydrates: monosaccharides (glucose), disaccharides (sucrose), polysaccharides (starch,
glycogen, cellulose). Proteins are polymers of amino acids linked by peptide bonds. Enzymes are biological
catalysts (mostly proteins). They speed up reactions by lowering activation energy. Enzyme activity is affected by
temperature, pH, substrate concentration. Lipids are fats, oils, steroids. Nucleic acids (DNA, RNA) store and
transfer genetic information. Primary metabolites are essential; secondary metabolites (alkaloids, pigments, etc.)
have ecological roles.
Q1. The most abundant organic compound on Earth is:
A. Protein
B. Cellulose
C. Starch
D. Glucose
✓ Correct Answer: B
Why this is correct: Cellulose, the structural polysaccharide of plant cell walls, is the most abundant organic polymer on
Earth.
✗ Why the other options are wrong:
• A, C and D are abundant but not more than cellulose.
Q2. The bond that links two amino acids is called a:
A. Glycosidic bond
B. Peptide bond
C. Hydrogen bond
D. Ester bond
✓ Correct Answer: B
Why this is correct: A peptide bond is a covalent bond formed between the carboxyl group of one amino acid and the amino
group of another.
✗ Why the other options are wrong:
• A joins sugars.
• C is weak and non-covalent.
• D joins fatty acids to glycerol.
Q3. Enzymes are mainly made of:
A. Carbohydrates
B. Proteins
C. Lipids
D. Nucleic acids
✓ Correct Answer: B
Why this is correct: Almost all enzymes are proteins (a few catalytic RNAs called ribozymes also exist).
✗ Why the other options are wrong:
• A, C and D are not the main structural basis of enzymes.
Q4. The inactive form of an enzyme is called:
A. Holoenzyme
B. Apoenzyme
C. Coenzyme
D. Substrate
✓ Correct Answer: B
Why this is correct: Apoenzyme is the protein part of an enzyme without its cofactor; it is catalytically inactive.
✗ Why the other options are wrong:
• A is the complete active enzyme.
NEET 2027 | High-Weightage Biology | Part 4 – Biomolecules to Evolution Page 3
, • C is an organic cofactor.
• D is the molecule on which the enzyme acts.
Q5. Which of the following is a disaccharide?
A. Glucose
B. Fructose
C. Sucrose
D. Starch
✓ Correct Answer: C
Why this is correct: Sucrose is a disaccharide made of glucose + fructose. Glucose and fructose are monosaccharides;
starch is a polysaccharide.
✗ Why the other options are wrong:
• A and B are monosaccharides.
• D is a polysaccharide.
Q6. The prosthetic group of haemoglobin is:
A. Globin
B. Haem (heme)
C. Iron only
D. Copper
✓ Correct Answer: B
Why this is correct: Haem (heme) is the iron-containing prosthetic group that binds oxygen in haemoglobin.
✗ Why the other options are wrong:
• A is the protein part.
• C is incomplete.
• D is present in haemocyanin, not haemoglobin.
Q7. Competitive inhibition of an enzyme can be overcome by:
A. Increasing enzyme concentration
B. Increasing substrate concentration
C. Decreasing temperature
D. Adding more inhibitor
✓ Correct Answer: B
Why this is correct: In competitive inhibition the inhibitor competes for the active site. Raising substrate concentration
out-competes the inhibitor.
✗ Why the other options are wrong:
• A helps but is not the classic way.
• C and D would not relieve competitive inhibition.
Q8. Which of the following is not a polysaccharide?
A. Starch
B. Glycogen
C. Cellulose
D. Maltose
✓ Correct Answer: D
Why this is correct: Maltose is a disaccharide (glucose + glucose). Starch, glycogen and cellulose are polymers of glucose.
✗ Why the other options are wrong:
• A, B and C are all polysaccharides.
Q9. The secondary structure of protein is stabilised mainly by:
A. Peptide bonds
B. Hydrogen bonds
C. Disulphide bonds
NEET 2027 | High-Weightage Biology | Part 4 – Biomolecules to Evolution Page 4
HIGH-WEIGHTAGE BIOLOGY
PART 4
BIOMOLECULES • STRUCTURAL ORGANISATION DIVERSITY • HEALTH • EVOLUTION •
FOOD PRODUCTION
140 Practice Questions with Full Explanations
Simple Language • Concept + Practice Practice
Inside This Book
✓ Clear short theory for every major topic
✓ 140 carefully chosen practice questions
✓ Detailed reason why the correct option is right
✓ Detailed reason why each wrong option is wrong
✓ Written in easy Class 8–9 level English
✓ Completes the high-weightage Biology series for NEET 2027
Topics: Biomolecules • Tissues & Anatomy • Plant & Animal Kingdom
Human Health & Diseases • Evolution • Food Production Strategies
, CONTENTS
1. Biomolecules — Theory + Q1 to Q25
2. Structural Organisation (Tissues, Morphology, Anatomy) — Theory + Q26 to Q50
3. Diversity of Living Organisms (Plant & Animal Kingdom) — Theory + Q51 to Q75
4. Human Health and Diseases + Microbes — Theory + Q76 to Q100
5. Evolution — Theory + Q101 to Q120
6. Strategies for Enhancement in Food Production — Theory + Q121 to Q140
Quick Revision Tips — Last page
How to Use This Book
1. First read the short theory of the topic carefully.
2. Then solve the questions of that topic.
3. Read why the correct answer is right and why the other options are wrong.
4. This builds real understanding and helps you avoid common mistakes in NEET.
NEET 2027 | High-Weightage Biology | Part 4 – Biomolecules to Evolution Page 2
, 1. BIOMOLECULES
Biomolecules are organic compounds present in living organisms. Major classes: Carbohydrates, Proteins, Lipids,
Nucleic acids. Carbohydrates: monosaccharides (glucose), disaccharides (sucrose), polysaccharides (starch,
glycogen, cellulose). Proteins are polymers of amino acids linked by peptide bonds. Enzymes are biological
catalysts (mostly proteins). They speed up reactions by lowering activation energy. Enzyme activity is affected by
temperature, pH, substrate concentration. Lipids are fats, oils, steroids. Nucleic acids (DNA, RNA) store and
transfer genetic information. Primary metabolites are essential; secondary metabolites (alkaloids, pigments, etc.)
have ecological roles.
Q1. The most abundant organic compound on Earth is:
A. Protein
B. Cellulose
C. Starch
D. Glucose
✓ Correct Answer: B
Why this is correct: Cellulose, the structural polysaccharide of plant cell walls, is the most abundant organic polymer on
Earth.
✗ Why the other options are wrong:
• A, C and D are abundant but not more than cellulose.
Q2. The bond that links two amino acids is called a:
A. Glycosidic bond
B. Peptide bond
C. Hydrogen bond
D. Ester bond
✓ Correct Answer: B
Why this is correct: A peptide bond is a covalent bond formed between the carboxyl group of one amino acid and the amino
group of another.
✗ Why the other options are wrong:
• A joins sugars.
• C is weak and non-covalent.
• D joins fatty acids to glycerol.
Q3. Enzymes are mainly made of:
A. Carbohydrates
B. Proteins
C. Lipids
D. Nucleic acids
✓ Correct Answer: B
Why this is correct: Almost all enzymes are proteins (a few catalytic RNAs called ribozymes also exist).
✗ Why the other options are wrong:
• A, C and D are not the main structural basis of enzymes.
Q4. The inactive form of an enzyme is called:
A. Holoenzyme
B. Apoenzyme
C. Coenzyme
D. Substrate
✓ Correct Answer: B
Why this is correct: Apoenzyme is the protein part of an enzyme without its cofactor; it is catalytically inactive.
✗ Why the other options are wrong:
• A is the complete active enzyme.
NEET 2027 | High-Weightage Biology | Part 4 – Biomolecules to Evolution Page 3
, • C is an organic cofactor.
• D is the molecule on which the enzyme acts.
Q5. Which of the following is a disaccharide?
A. Glucose
B. Fructose
C. Sucrose
D. Starch
✓ Correct Answer: C
Why this is correct: Sucrose is a disaccharide made of glucose + fructose. Glucose and fructose are monosaccharides;
starch is a polysaccharide.
✗ Why the other options are wrong:
• A and B are monosaccharides.
• D is a polysaccharide.
Q6. The prosthetic group of haemoglobin is:
A. Globin
B. Haem (heme)
C. Iron only
D. Copper
✓ Correct Answer: B
Why this is correct: Haem (heme) is the iron-containing prosthetic group that binds oxygen in haemoglobin.
✗ Why the other options are wrong:
• A is the protein part.
• C is incomplete.
• D is present in haemocyanin, not haemoglobin.
Q7. Competitive inhibition of an enzyme can be overcome by:
A. Increasing enzyme concentration
B. Increasing substrate concentration
C. Decreasing temperature
D. Adding more inhibitor
✓ Correct Answer: B
Why this is correct: In competitive inhibition the inhibitor competes for the active site. Raising substrate concentration
out-competes the inhibitor.
✗ Why the other options are wrong:
• A helps but is not the classic way.
• C and D would not relieve competitive inhibition.
Q8. Which of the following is not a polysaccharide?
A. Starch
B. Glycogen
C. Cellulose
D. Maltose
✓ Correct Answer: D
Why this is correct: Maltose is a disaccharide (glucose + glucose). Starch, glycogen and cellulose are polymers of glucose.
✗ Why the other options are wrong:
• A, B and C are all polysaccharides.
Q9. The secondary structure of protein is stabilised mainly by:
A. Peptide bonds
B. Hydrogen bonds
C. Disulphide bonds
NEET 2027 | High-Weightage Biology | Part 4 – Biomolecules to Evolution Page 4
