What is Nutrition in Plants Class 7: Complete Guide for NCERT Students

Definition: What is Nutrition in Plants?

Nutrition in plants refers to the process by which plants obtain and use food to grow and carry out life functions. Unlike animals, most plants make their own food through a process called photosynthesis. This involves using sunlight, water, and carbon dioxide to create glucose, a type of sugar that provides energy.

Plants need nutrients to build cells, repair tissues, and perform various activities essential for survival. This chapter in Class 7 NCERT Science explains these concepts clearly to help students understand how plants sustain themselves.

Types of Nutrition in Plants

Plants have two main types of nutrition:

• Autotrophic Nutrition: Plants prepare their own food using sunlight. They are called autotrophs. Most green plants use photosynthesis.
• Heterotrophic Nutrition: Some plants cannot make their own food and depend on other organisms. These are heterotrophs.

Autotrophic Nutrition

Plants use chlorophyll in their leaves to capture sunlight. They combine water from the soil and carbon dioxide from the air to make glucose and oxygen.

Heterotrophic Nutrition

Examples include:

• Parasitic plants like Cuscuta, which absorb nutrients from host plants.
• Saprotrophic plants like fungi, which feed on dead organic matter.
• Insectivorous plants like the Venus flytrap, which trap insects for nutrients.

How Photosynthesis Works: The Food-Making Process

Photosynthesis is the process by which green plants make food. It occurs mainly in the leaves, inside cells containing chlorophyll.

The basic formula for photosynthesis is:

$$6CO_2 + 6H_2O + light ightarrow C_6H_{12}O_6 + 6O_2$$

This means six molecules of carbon dioxide and six molecules of water, using light energy, produce one molecule of glucose and six molecules of oxygen.

Steps of Photosynthesis:

• Leaves take in carbon dioxide from the air.
• Roots absorb water from the soil.
• Chlorophyll captures sunlight.
• Energy converts carbon dioxide and water into glucose.
• Oxygen is released as a byproduct.

This glucose is used by plants for energy and growth.

Comparison: Autotrophic vs Heterotrophic Nutrition

Here is a simple comparison table to understand the differences:

This comparison helps Class 7 students remember key differences for exams.

Special Types of Nutrition in Plants

Besides photosynthesis, some plants have unique nutrition methods:

• Parasitic Nutrition: Plants like Cuscuta attach to host plants and absorb nutrients directly.
• Saprotrophic Nutrition: Fungi and some bacteria feed on dead organic matter by secreting enzymes.
• Insectivorous Nutrition: Plants like pitcher plants trap insects to supplement nutrients, especially nitrogen.

These adaptations help plants survive in environments where nutrients are scarce.

Why is Understanding Nutrition in Plants Important for Class 7 Students?

Nutrition in plants is a fundamental topic in the NCERT Class 7 Science syllabus. Understanding this chapter helps students:

• Grasp how plants sustain life on Earth.
• Learn about the role of sunlight and chlorophyll.
• Prepare for exams with clear concepts and examples.
• Appreciate plant adaptations and biodiversity.

Teachers often ask questions on photosynthesis, types of nutrition, and special plants, so mastering this topic boosts exam confidence.