Class 7 Science

Chapter 1: Nutrition in Plants

STAGE 0: Foundation / Basics

All living organisms need food to live. Food gives energy, helps in growth, repair of the body, and keeps us healthy.

The process by which organisms take food and use it for growth and energy is called Nutrition.

Plants prepare their own food, while animals depend on plants or other animals.

STAGE 1: Modes of Nutrition in Plants

Plants show different modes of nutrition:

• Autotrophic Nutrition
• Heterotrophic Nutrition

Autotrophic Nutrition

Green plants prepare their own food using:

• Sunlight
• Carbon dioxide
• Water
• Chlorophyll

This process is called Photosynthesis.

Carbon dioxide + Water → Food + Oxygen

Photosynthesis mainly takes place in the leaves of plants.

Heterotrophic Nutrition

Some plants cannot make their own food. They depend on other plants or animals. This type of nutrition is called Heterotrophic Nutrition.

Types of Heterotrophic Nutrition:

• Parasitic – Example: Cuscuta (Amarbel)
• Saprophytic – Example: Mushroom
• Insectivorous – Example: Pitcher plant
• Symbiotic – Example: Lichen

STAGE 2: NCERT Textbook Questions & Answers

Q1. Why do plants need nutrients?

Plants need nutrients for growth, repair, energy, and to stay healthy.

Q2. What is photosynthesis?

Photosynthesis is the process by which green plants make their own food using sunlight, carbon dioxide, and water.

Q3. Name one parasitic plant.

Cuscuta (Amarbel).

STAGE 3: Exam-Oriented Questions

1. Fill in the blanks:

• Green plants are called autotrophs.
• Photosynthesis takes place in the leaves.

2. Very Short Answer:

Which gas is released during photosynthesis?
Answer: Oxygen

Quick Revision Points

• Nutrition is necessary for life
• Plants prepare food by photosynthesis
• Chlorophyll is essential for photosynthesis
• Some plants depend on others for food