NEET 2027
HIGH-WEIGHTAGE BIOLOGY
PART 1
HUMAN PHYSIOLOGY
80 Practice Questions with Full Explanations
Simple Language • Concept + Practice Practice
Inside This Book
✓ Clear short theory for every topic of Human Physiology
✓ 80 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
✓ Perfect for NEET 2027 preparation and quick revision
Topics: Digestion • Breathing • Circulation • Excretion
Locomotion • Neural Control • Endocrine System
, CONTENTS
1. Digestion and Absorption — Theory + Questions 1–12
2. Breathing and Exchange of Gases — Theory + Questions 13–22
3. Body Fluids and Circulation — Theory + Questions 23–34
4. Excretory Products and Their Elimination — Theory + Questions 35–44
5. Locomotion and Movement — Theory + Questions 45–52
6. Neural Control and Coordination — Theory + Questions 53–62
7. Chemical Coordination (Endocrine System) — Theory + Questions 63–80
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 the explanation of the correct answer and also why other options are wrong.
4. This way you will understand the concept deeply and avoid common mistakes.
NEET 2027 | High-Weightage Biology | Part 1 – Human Physiology Page 2
, 1. DIGESTION AND ABSORPTION
Digestion is the process of breaking large food molecules into small ones so that they can be absorbed into the
blood. The alimentary canal is a long tube: Mouth → Pharynx → Oesophagus → Stomach → Small intestine →
Large intestine → Anus. Accessory organs (liver, gall bladder, pancreas) help in digestion but food does not pass
through them.
Key points to remember:
• Mouth: Salivary amylase starts starch digestion. Food becomes bolus.
• Stomach: HCl + Pepsin. Proteins start getting digested. Food becomes chyme.
• Small intestine: Main site of digestion and absorption. Bile (from liver) emulsifies fat. Pancreatic juice has trypsin,
amylase, lipase. Intestinal juice finishes digestion.
• Villi in small intestine increase surface area for absorption.
• Final products: Carbohydrates → Glucose | Proteins → Amino acids | Fats → Fatty acids + Glycerol.
• Bile has NO enzymes. It only does emulsification of fats.
Q1. Salivary amylase acts on which substrate?
A. Proteins
B. Starch
C. Fats
D. Cellulose
✓ Correct Answer: B
Why this is correct: Salivary amylase (also called ptyalin) is present in saliva. It begins the chemical digestion of starch by
breaking it into maltose in the mouth.
✗ Why the other options are wrong:
• A is wrong because proteins are digested by pepsin (stomach) and trypsin (pancreas).
• C is wrong because fats are digested by lipase enzyme.
• D is wrong because human beings do not produce cellulase, so cellulose cannot be digested.
Q2. Which of the following is correct about bile?
A. Bile contains enzymes that digest fat
B. Bile helps in emulsification of fats
C. Bile is acidic in nature
D. Bile is secreted by the pancreas
✓ Correct Answer: B
Why this is correct: Bile does not contain any digestive enzyme. Its main role is emulsification – breaking large fat globules
into tiny droplets so that lipase can act on a larger surface area.
✗ Why the other options are wrong:
• A is wrong because bile has no enzymes at all.
• C is wrong because bile is alkaline (basic). It helps neutralise the acidic chyme coming from the stomach.
• D is wrong because bile is produced by the liver and stored in the gall bladder, not by the pancreas.
Q3. The enzyme pepsin works best in:
A. Alkaline medium
B. Acidic medium
C. Neutral medium
D. Any medium
✓ Correct Answer: B
Why this is correct: Pepsin is secreted as inactive pepsinogen. HCl in the stomach converts it into active pepsin and also
provides the acidic pH (around 1.8–2.0) needed for its activity.
✗ Why the other options are wrong:
• A is wrong because alkaline medium is required by enzymes of the small intestine (trypsin, etc.).
• C is wrong because neutral pH is not suitable for pepsin.
• D is wrong because enzymes are highly specific for pH.
NEET 2027 | High-Weightage Biology | Part 1 – Human Physiology Page 3
HIGH-WEIGHTAGE BIOLOGY
PART 1
HUMAN PHYSIOLOGY
80 Practice Questions with Full Explanations
Simple Language • Concept + Practice Practice
Inside This Book
✓ Clear short theory for every topic of Human Physiology
✓ 80 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
✓ Perfect for NEET 2027 preparation and quick revision
Topics: Digestion • Breathing • Circulation • Excretion
Locomotion • Neural Control • Endocrine System
, CONTENTS
1. Digestion and Absorption — Theory + Questions 1–12
2. Breathing and Exchange of Gases — Theory + Questions 13–22
3. Body Fluids and Circulation — Theory + Questions 23–34
4. Excretory Products and Their Elimination — Theory + Questions 35–44
5. Locomotion and Movement — Theory + Questions 45–52
6. Neural Control and Coordination — Theory + Questions 53–62
7. Chemical Coordination (Endocrine System) — Theory + Questions 63–80
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 the explanation of the correct answer and also why other options are wrong.
4. This way you will understand the concept deeply and avoid common mistakes.
NEET 2027 | High-Weightage Biology | Part 1 – Human Physiology Page 2
, 1. DIGESTION AND ABSORPTION
Digestion is the process of breaking large food molecules into small ones so that they can be absorbed into the
blood. The alimentary canal is a long tube: Mouth → Pharynx → Oesophagus → Stomach → Small intestine →
Large intestine → Anus. Accessory organs (liver, gall bladder, pancreas) help in digestion but food does not pass
through them.
Key points to remember:
• Mouth: Salivary amylase starts starch digestion. Food becomes bolus.
• Stomach: HCl + Pepsin. Proteins start getting digested. Food becomes chyme.
• Small intestine: Main site of digestion and absorption. Bile (from liver) emulsifies fat. Pancreatic juice has trypsin,
amylase, lipase. Intestinal juice finishes digestion.
• Villi in small intestine increase surface area for absorption.
• Final products: Carbohydrates → Glucose | Proteins → Amino acids | Fats → Fatty acids + Glycerol.
• Bile has NO enzymes. It only does emulsification of fats.
Q1. Salivary amylase acts on which substrate?
A. Proteins
B. Starch
C. Fats
D. Cellulose
✓ Correct Answer: B
Why this is correct: Salivary amylase (also called ptyalin) is present in saliva. It begins the chemical digestion of starch by
breaking it into maltose in the mouth.
✗ Why the other options are wrong:
• A is wrong because proteins are digested by pepsin (stomach) and trypsin (pancreas).
• C is wrong because fats are digested by lipase enzyme.
• D is wrong because human beings do not produce cellulase, so cellulose cannot be digested.
Q2. Which of the following is correct about bile?
A. Bile contains enzymes that digest fat
B. Bile helps in emulsification of fats
C. Bile is acidic in nature
D. Bile is secreted by the pancreas
✓ Correct Answer: B
Why this is correct: Bile does not contain any digestive enzyme. Its main role is emulsification – breaking large fat globules
into tiny droplets so that lipase can act on a larger surface area.
✗ Why the other options are wrong:
• A is wrong because bile has no enzymes at all.
• C is wrong because bile is alkaline (basic). It helps neutralise the acidic chyme coming from the stomach.
• D is wrong because bile is produced by the liver and stored in the gall bladder, not by the pancreas.
Q3. The enzyme pepsin works best in:
A. Alkaline medium
B. Acidic medium
C. Neutral medium
D. Any medium
✓ Correct Answer: B
Why this is correct: Pepsin is secreted as inactive pepsinogen. HCl in the stomach converts it into active pepsin and also
provides the acidic pH (around 1.8–2.0) needed for its activity.
✗ Why the other options are wrong:
• A is wrong because alkaline medium is required by enzymes of the small intestine (trypsin, etc.).
• C is wrong because neutral pH is not suitable for pepsin.
• D is wrong because enzymes are highly specific for pH.
NEET 2027 | High-Weightage Biology | Part 1 – Human Physiology Page 3
