10TH CBSE LIFE PROCESS SHORT NOTES

Life Processes – Interactive Study Notes

1. Life Processes

Life processes are the activities necessary to maintain life. Main life processes:

• Nutrition
• Respiration
• Transportation
• Excretion
• Growth

2. Characteristics of Living Organisms

• Cellular organization
• Sensitivity to stimuli
• Respiration
• Metabolism
• Homeostasis
• Growth
• Reproduction

3. Nutrition

Nutrition is the process of intake and utilization of food. Types of nutrients:

• Carbohydrates
• Proteins
• Fats
• Vitamins
• Minerals

4. Modes of Nutrition

Autotrophic: Organisms prepare their own food using sunlight. Example: Plants

Heterotrophic: Organisms depend on other organisms for food. Example: Animals

5. Photosynthesis

Photosynthesis converts carbon dioxide and water into glucose using sunlight. Equation: 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂ Requirements:

• Sunlight
• Carbon dioxide
• Water
• Chlorophyll

6. Human Digestive System

Main organs:

• Mouth
• Oesophagus
• Stomach
• Small intestine
• Large intestine
• Rectum

7. Digestion

Food is broken down into simpler substances:

• Carbohydrates → Glucose
• Proteins → Amino acids
• Fats → Fatty acids + Glycerol

Digestive enzymes:

• Amylase
• Pepsin
• Lipase

8. Absorption

Absorption occurs mainly in the small intestine. Structures called villi increase the surface area for absorption. Nutrients absorbed:

• Glucose
• Amino acids
• Fatty acids
• Vitamins

9. Respiration

Respiration is the breakdown of food to release energy. Equation: Glucose + Oxygen → Carbon dioxide + Water + Energy Energy is stored as ATP.

10. Gas Exchange

Plants exchange gases through:

• Stomata
• Lenticels
• Root hairs

Animals use:

• Lungs
• Gills
• Tracheae
• Skin