Nutrition in Plants Class 7 Notes – Quick Revision

Nutrition in Plants Class 7 notes explain how green plants make food by photosynthesis and how some organisms obtain nutrition in other ways. The most important ideas are autotrophic and heterotrophic nutrition, chlorophyll, carbon dioxide, water, sunlight, parasites, saprotrophs, symbiosis and nitrogen fixation.

Updated for 2026–27: this page preserves the familiar “Nutrition in Plants” topic because students still search for and revise it, but NCERT’s current Class 7 Science textbook sequence has changed. Use these notes for concept revision and follow the current NCERT/CBSE textbook used by your school for the latest chapter order.

Concept	Quick meaning
Autotrophic nutrition	Green plants make food from carbon dioxide and water using sunlight and chlorophyll.
Heterotrophic nutrition	Organisms obtain ready-made food from other organisms.
Photosynthesis	Food-making process in green parts of plants.
Parasite	Obtains nutrition from a living host.
Saprotroph	Obtains nutrients from dead and decaying matter.
Symbiosis	Two organisms live together and both may benefit.
Nitrogen fixation	Conversion of atmospheric nitrogen into forms plants can use.

Topics Covered in These Notes

• Modes of nutrition in plants
• Photosynthesis and the role of chlorophyll, sunlight, carbon dioxide and water
• Parasites and insectivorous plants
• Saprotrophic nutrition
• Symbiotic relationships and Rhizobium
• Nitrogen fixation and replenishment of soil nutrients

Watch & Learn: English + Hindi Video Lessons

Choose the language that helps you learn best. These videos are selected for concept clarity rather than board-specific exam promotion, so they can also help learners outside CBSE and India.

English: Plant Nutrition & Photosynthesis

This middle-school lesson from Khan Academy explains why plants are autotrophs, introduces photosynthesis, and clarifies the role of soil, fertilisers and manures. It works well as a global concept-first introduction before reading the detailed notes.

हिंदी: पादपों में पोषण – Class 7 Science

This Hindi lesson from Magnet Brains Hindi Medium gives a full-chapter revision of plant nutrition, including modes of nutrition, photosynthesis, Cuscuta, insectivorous plants, saprotrophs, symbiosis and replenishment of soil nutrients.

Tip: Watch one language version first, then use the notes and revision checklist below to test what you understood.

Modes of Nutrition in Plants

Nutrition is the mode of taking food by an organism and its utilisation by the body.

• Nutrition is very important as the nutrients from the food consumed enables living organisms to build their bodies and grow.
• Nutrition helps to repair damaged parts and organs.
• Nutrition also provides energy for carrying out various functions.

Modes of Nutrition

On the basis of a different mode of nutrition, organisms are categorised into two major types, i.e.

Autotrophs: Green plants containing chlorophyll can make food from carbon dioxide and water using light energy. This mode of nutrition is called autotrophic nutrition.

Heterotrophs: Organisms that cannot manufacture all the food they need from simple inorganic substances depend on other organisms for nutrition. Animals, fungi and parasitic plants are examples of heterotrophs.

Why Do Plants Need Nutrition?

Plants need raw materials and mineral nutrients for growth, repair and reproduction. Green plants capture light energy and use it to make carbohydrate-rich food by photosynthesis; they also absorb water and mineral nutrients through their roots.

Photosynthesis – Food-Making Process in Plants

The process by which green plants use carbon dioxide and water to make food in the presence of sunlight and chlorophyll is called photosynthesis.

Word equation: Carbon dioxide + Water → Glucose + Oxygen (in the presence of sunlight and chlorophyll).

Site of Photosynthesis

Photosynthesis takes place mainly in leaves because their cells contain chloroplasts with chlorophyll. Other green parts, such as some young stems, can also photosynthesise when they contain chlorophyll.

Other Modes of Nutrition in Plants

There are some plants which do not contain chlorophyll in them and thus, cannot prepare their own food. These plants obtain their food from other plants or animals, i.e. they are heterotrophic in nature.

Symbiotic Relationship

Organisms that live together and share their shelter and nutrients are said to be in a symbiotic relationship.

• Certain fungi live in the roots of trees.
• The tree provides nutrients to the fungus and, in return, receives help from it to take up water and nutrients from the soil.
• This association works well for both the fungi and the tree.
• Another most common example is of Rhizobium bacteria.
• They reside in the root nodules of leguminous plants.
• The bacteria provide a plant with nitrogen that they fix and in turn, they get shelter and food from the plant.

Rhizobium

• Rhizobium is a type of bacteria that convert atmospheric nitrogen into a soluble form that can be utilised by plants (nitrogen fixation).
• It usually resides in the roots of leguminous plants like peas, gram, moong etc and is instrumental in providing these plants with a rich source of nitrogen.

Nitrogen Fixation

• Nitrogen is an important nutrient required for soil and for plants.
• However, nitrogen in the atmosphere is not easily accessible.

The process by which nitrogen is converted into a form that can be used by plants and other living organisms is called nitrogen fixation.

Parasites

A parasite obtains some or all of its nutrition from a living organism called the host. The parasite benefits while the host may be weakened because nutrients are diverted from it.

• Cuscuta (Amarbel) is a familiar example of a parasitic plant.
• It has little or no chlorophyll and obtains ready-made food from the host plant through specialised connections.

Saprotrophic Nutrition

Organisms which rely on dead and decaying matter for their food are called Saprotrophs.

• This mode of nutrition is called saprotrophic nutrition.
• For example, Fungi.
• Fungi secrete digestive juices on the dead and decaying matter and convert it into a solution.
• Then they absorb the nutrients from it.

Insectivorous Plants :

Plants that feed on insects are called Insectivorous plants.

• These plants are green and carry out photosynthesis.
• Many grow in soils poor in available nitrogen.
• They trap and digest insects mainly to obtain mineral nutrients such as nitrogen.
• Their leaves are modified to attract and capture prey.
• Examples include the pitcher plant and Venus flytrap.

How Are Nutrients Replenished in the Soil?

• Plants absorb water and mineral nutrients from the soil for growth and other life processes.
• Important soil nutrients include nitrogen, phosphorus, potassium and several other elements.
• Soil fertility can be maintained through manure, compost, suitable fertilisers, crop rotation and biological nitrogen fixation.
• Plants require essential elements in different amounts: macronutrients are needed in relatively larger quantities and micronutrients in smaller quantities.
• Leguminous plants associated with Rhizobium help add biologically fixed nitrogen to the soil system.

5-Minute Revision Checklist

• Define autotrophic and heterotrophic nutrition in one line each.
• Write the word equation for photosynthesis without looking at the notes.
• Explain the difference between a parasite, a saprotroph and an insectivorous plant.
• State how Rhizobium helps leguminous plants.
• Name two ways soil nutrients can be replenished.

Related Class 7 Science Resources

• NCERT Solutions – Nutrition in Plants
• Nutrition in Animals Class 7 Notes
• Acids, Bases and Salts Class 7 Notes
• Physical and Chemical Changes Class 7 Notes

Nutrition in Plants Class 7 FAQs

What is nutrition in plants?

Plant nutrition is the process by which plants obtain the materials and energy needed for growth and other life functions. Green plants manufacture food by photosynthesis and absorb water and mineral nutrients from the soil.

What are the requirements for photosynthesis?

Photosynthesis requires carbon dioxide, water, light and chlorophyll. The process produces glucose and releases oxygen.

What is the difference between a parasite and a saprotroph?

A parasite obtains nutrition from a living host, whereas a saprotroph obtains nutrients from dead and decaying organic matter.

How are nutrients replenished in soil?

Soil nutrients can be replenished through manure, compost, appropriate fertilisers, crop rotation and biological nitrogen fixation. Rhizobium associated with leguminous plants helps fix atmospheric nitrogen.