CBSE Class 7 Answered

Hi Shanthini,

• Nutrition is the mode of taking in food by an organism and its utilisation by the body.
• Plants prepare their own food in the presence of sunlight and the green pigment chlorophyll by a process termed as photosynthesis.
• During photosynthesis, chlorophyll containing cells of leaves use carbon dioxide and water in the presence of sunlight to synthesise carbohydrates along with the release of oxygen.
• The soil contains some nitrogen-fixing bacteria which convert gaseous nitrogen into a more usable form and release it into the soil.
• Certain plants convert carbohydrate into oils and store them in seeds. Example: Sunflower seeds. The oil obtained from plant seeds is commonly known as vegetable oil.
• Types of heterotrophic nutrition in plants- Parasitic, Insectivorous, Saprophytic and Symbiotic association.
• Fertilisers and manures which contain phosphorus, potassium, nitrogen etc. are constantly added to the soil from time to time to enrich the soil.

For elaboration of the above points, kindly register with www.topperlearning.com and get detailed topic notes, revision notes, question banks, sample papers and video lessons.