CBSE Class 10 Biology Notes (Board Exam Edition)
Complete Science Biology Notes – All Chapters
Designed for CBSE Board Preparation
Chapter 1: Life Processes
Introduction
Life processes are the basic activities performed by living organisms to maintain life. These include:
• Nutrition
• Respiration
• Transportation
• Excretion
Nutrition
Nutrition is the process of taking food and utilizing it for energy and growth.
Types of Nutrition
1. Autotrophic Nutrition
• Organisms prepare their own food.
• Example: Green plants
• Requires:
• Sunlight
• Chlorophyll
• Carbon dioxide
• Water
Photosynthesis Equation
6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
Important Points
• Chlorophyll traps sunlight.
• Stomata help in gas exchange.
1
, • Oxygen is released as a by-product.
2. Heterotrophic Nutrition
Organisms depend on others for food.
Types:
• Holozoic – Human beings
• Saprophytic – Fungi
• Parasitic – Cuscuta
Human Digestive System
Main Organs
• Mouth
• Oesophagus
• Stomach
• Small intestine
• Large intestine
Digestive Enzymes
Organ Enzyme Function
Salivary glands Salivary amylase Digests starch
Stomach Pepsin Digests proteins
Pancreas Trypsin Protein digestion
Small intestine Lipase Fat digestion
Important Facts
• Hydrochloric acid kills germs.
• Bile juice emulsifies fats.
• Small intestine absorbs nutrients.
Respiration
Respiration is the breakdown of food to release energy.
2
Complete Science Biology Notes – All Chapters
Designed for CBSE Board Preparation
Chapter 1: Life Processes
Introduction
Life processes are the basic activities performed by living organisms to maintain life. These include:
• Nutrition
• Respiration
• Transportation
• Excretion
Nutrition
Nutrition is the process of taking food and utilizing it for energy and growth.
Types of Nutrition
1. Autotrophic Nutrition
• Organisms prepare their own food.
• Example: Green plants
• Requires:
• Sunlight
• Chlorophyll
• Carbon dioxide
• Water
Photosynthesis Equation
6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
Important Points
• Chlorophyll traps sunlight.
• Stomata help in gas exchange.
1
, • Oxygen is released as a by-product.
2. Heterotrophic Nutrition
Organisms depend on others for food.
Types:
• Holozoic – Human beings
• Saprophytic – Fungi
• Parasitic – Cuscuta
Human Digestive System
Main Organs
• Mouth
• Oesophagus
• Stomach
• Small intestine
• Large intestine
Digestive Enzymes
Organ Enzyme Function
Salivary glands Salivary amylase Digests starch
Stomach Pepsin Digests proteins
Pancreas Trypsin Protein digestion
Small intestine Lipase Fat digestion
Important Facts
• Hydrochloric acid kills germs.
• Bile juice emulsifies fats.
• Small intestine absorbs nutrients.
Respiration
Respiration is the breakdown of food to release energy.
2
