CBSE Class 7 Science Revision Notes Chapter 1

Class 7 Science Chapter 1 Notes

CBSE Class 7 Science Revision Notes Chapter 1 – Nutrition in Plants

Extramarks provide revision notes that help students understand the processes and concepts covered in Class 7 Science Chapter 1 Nutrition in Plants. These notes give an overall overview of the nutrients and minerals needed by the plants to grow in a healthy way and the repercussions for the soil. This chapter also explains how nutrients are replenished in the soil.

The Class 7 Science Chapter 1 Notes provided by Extramarks cover all the above-mentioned topics and much more. Students can examine these notes, learn a lot about this chapter, and utilise them for their revision.

Revision Notes for CBSE Class 7 Science Chapter 1

Access Class 7 Science Chapter – 1 – Nutrition in Plants Notes

Food contains components like carbohydrates, proteins, fats, vitamins, and minerals. These constituents of food are called nutrients. Every living organism needs food to survive. Plants can produce their food through the process of photosynthesis.


The only organisms that can produce food for themselves by utilising water, carbon dioxide, and minerals are plants.

  • The plant absorbs the raw materials from its environment. The nutrients give living organisms the energy they need to carry out life processes and help them build their bodies, grow, and repair damaged parts of their bodies. Nutrition is the means of obtaining food from an organism and using it by its body. The process of nutrition in which organisms use basic materials to produce food for themselves is called autotrophic nutrition. Hence, plants are considered to be autotrophs.
  • Animals and numerous organisms consume the food produced by plants. These organisms are therefore called heterotrophs.


  • As leaves are considered to be the food factories of the plant it is necessary that all the raw materials reach the leaves. The roots absorb water and minerals present in the soil and transport them to the leaves.
  • The tiny pores on the surface of leaves are the openings from which carbon dioxide is absorbed from the air. Guard cells surround the pores. Those pores are known as stomata.
  • The vessels transfer water and minerals to the leaves, which look like pipes all over the root, the stem, the branches, and the leaves. The vessels provide a constant path or passage for the nutrients to flow to the leaf.
  • A green pigment present in the leaves is called chlorophyll. The energy of the sunlight is collected by leaves with the help of chlorophyll present in them. This energy is used to produce food from carbon dioxide and water.
  • The production of food takes place in the presence of sunlight, therefore, it is called photosynthesis. Chlorophyll, sunlight, carbon dioxide, and water are essential to accomplish the process of photosynthesis.
  • Solar energy is collected by the leaves and accumulated by the plant in the form of food. Therefore, the sun is the supreme source of energy for all living organisms.


  • Fungi is an organism that secretes digestive juices on dead and decaying matter and transforms it into a solution.
  • The process of nutrition in which organisms take in nutrients from dead and decaying matter is called saprotrophic nutrition. The organisms with such a saprotrophic means of nutrition are called saprotrophs.
  • Fungi breed on pickles, leather, clothes, etc., that are abandoned for a long time in hot and humid weather. During monsoons, fungi ruin many surfaces. Normally, fungal spores exist in the air. They germinate and grow on wet and warm things.
  • A few organisms exist together and share both shelter and nutrients. This connection is known as symbiosis. For instance, a fungus named ‘Mycorrhizal fungi’ lives within the roots of plants.

Class 7 Science Chapter 1: Nutrition in Plants – In a Nutshell

Synthesis of Plant Food Other Than Carbohydrates

Plants synthesise carbohydrates during the process of photosynthesis. Carbon, hydrogen, and oxygen together make up carbohydrates. Fats and proteins are further synthesised. And protein is a nitrogenous substance that consists of nitrogen.

Class 7 Science Chapter 1 Notes are extremely useful to prepare for the exams. These notes will help to gain an in-depth understanding and build the confidence of the students. It will help them understand the topic and retain the information easily.

The concepts of nutrition are briefly described in Class 7 Science Chapter 1 Notes along with their meaning and importance, as well as the growth and well-being of plants. Plants absorb nutrients and utilise them for their growth through a process called nutrition.

The nutrition of plants depends on the process of photosynthesis. Chlorophyll plays a significant part in photosynthesis and gives a green colour to plants. It helps plants by preparing their food and getting their nutrition through the process of photosynthesis. The notes have discussed these basic aspects of the chapter.

Chlorophyll and chloroplast have been explained in Class 7 Science Chapter 1 Notes. Students will gain a greater understanding of the photosynthesis process as mentioned above. These notes cover the fundamental concepts of this chapter and help in setting a foundation in the minds of students for further topics.

Class 7 Science Chapter 1 Notes also explain the different modes of nutrition in distinct types of plants. This will help students learn more about these varieties of plants and organisms with their nutrition requirements. Examples of each explanation will help the students get an overall idea of this chapter.

These Class 7 Science Chapter 1 Notes elaborate on the symbiotic relationship between organisms and how two organisms depend on each other for nourishment.

FAQs (Frequently Asked Questions)

1. What is an algae?

 Slimy, green patches in ponds or still water bodies are generally formed by the growth of organisms called algae.

2. What is symbiosis?

Some organisms exist together and share both shelter and nutrients. This relationship is called symbiosis

3. How do soil nutrients replenish themselves?

Replenishment of nutrients takes place in the following way:

  • Plants soak up different minerals and nutrients present in the soil. Therefore, the number of minerals and nutrients in the soil deteriorates.
  • Nutrients such as nitrogen, potassium, phosphorus, etc. are present in fertilisers and manures. The soil can be enriched by adding nutrients every once in a while.
  • If the nutrient requirements of plants are fulfilled, the plants grow in a healthy manner. The amount of nitrogen deteriorates from the soil as the crop plants imbibe ample nitrogen from the soil.
  • Plants are incapable of using nitrogen gas, which is sufficiently present in the air as it causes carbon dioxide. Nitrogen can be absorbed by plants only in a soluble form.
  • Atmospheric nitrogen can be transformed into a usable form by a bacterium called Rhizobium. Rhizobium lives in the roots of a gram, peas, moong, beans, and other legumes, providing them with nitrogen as they are incapable of making their own food.
  • The bacteria, in exchange, receive food and shelter from the plant. This relationship is called symbiosis. Farmers can cut down on the use of nitrogenous fertilisers wherever leguminous plants are grown. Almost all of the pulses (dals) are acquired from leguminous plants.

Chapter 1 of Class 7 Science states that nearly all plants are autotrophs. Some of the plants are parasitic or saprotrophic which means these plants derive their nutrition from several other organisms. Animals depend on plants and other animals. Therefore, all animals are considered heterotrophs. Students can access Class 7 Science Chapter 1 Notes from Extramarks to score better.