Class 10 Science Chapter 1: Life Processes – Part 1 Notes (Maharashtra Board)

🔍 Detailed Explanation of Concepts

What are Life Processes?

Life processes are vital biological functions carried out by all living organisms to maintain life. These include nutrition, respiration, transportation, and excretion. In this chapter, the focus is on nutrition and respiration.

🍃 Nutrition

Nutrition is the process of obtaining energy and materials for cellular activities.

• Autotrophic Nutrition: Organisms synthesize their own food (e.g., plants)
• Heterotrophic Nutrition: Organisms depend on others for food (e.g., humans, animals)

Photosynthesis

Process by which green plants prepare food using chlorophyll, sunlight, CO₂, and water.

Equation: 6CO₂ + 6H₂O + Sunlight → C₆H₁₂O₆ + 6O₂

Human Nutrition

Involves ingestion, digestion, absorption, assimilation, and egestion.

💨 Respiration

Respiration is the process by which organisms break down glucose to release energy in the form of ATP.

Types of Respiration

• Aerobic Respiration: Occurs in presence of oxygen; produces CO₂, H₂O, and more energy.
• Anaerobic Respiration: Occurs without oxygen; produces less energy and end products like alcohol or lactic acid.

Equation: C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + Energy (ATP)

Human Respiratory System

Includes nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles, and alveoli. Exchange of gases occurs in alveoli.

📘 Important Definitions / Key Terms

• Nutrition: The process of obtaining and utilizing food
• Photosynthesis: Food production process in green plants
• Respiration: Energy release from glucose
• ATP: Adenosine Triphosphate – Energy currency of the cell

📄 Chapter Summary

This chapter introduces two fundamental life processes: nutrition and respiration. Nutrition is essential for energy and material supply to living organisms. Plants exhibit autotrophic nutrition through photosynthesis, using sunlight, water, and carbon dioxide. Heterotrophs like humans depend on plants and animals for food. The human digestive system includes several organs that work together to break down and absorb food. Respiration is the cellular process of converting glucose into energy in the form of ATP. It may be aerobic (with oxygen) or anaerobic (without oxygen). The human respiratory system includes various organs such as the lungs, which enable the exchange of oxygen and carbon dioxide. Understanding these processes helps explain how energy flows and sustains life within organisms.

📚 Board Exam Questions

🟩 1 Mark

• Define photosynthesis.
• What is ATP?

🟨 2 Marks

• Differentiate between autotrophic and heterotrophic nutrition.
• Write the chemical equation for aerobic respiration.

🟧 3 Marks

• Describe the human respiratory system.
• Explain the role of enzymes in digestion.

🟥 4 Marks

• Explain the entire process of nutrition in humans.
• Compare aerobic and anaerobic respiration with examples.

📊 Diagram-Based

• Labelled diagram of the human digestive system
• Diagram of the human respiratory system

❓ FAQ Section