Question

Give a brief description of the process of synthesis of food in green plants.
NCERT Solutions for Class 7th Science Chapter 1 Nutrition in Plants Page 9 Exercise Question 4

Answer 1

Photosynthesis is defined as the process in which the chlorophyll- containing plant cells synthesize food in the form of carbohydrates, using carbon dioxide and water in the presence of solar energy.

Sources of raw materials required for photosynthesis:

(a)  Water is taken in, from the roots of the plant and is transported to the leaves.

(b)  Carbon dioxide from the air enters the leaves through the pores called stomata and diffuses to the cells containing chlorophyll.

(c)  Solar energy is used to break water into hydrogen and oxygen. This hydrogen is combined with carbon dioxide to form food for the plants, which is ultimately used by the animals as well.

Thus , photosynthesis can be represented by the following equation.

Carbon dioxide + Water --- Sunlight, Cholorophyll -----> Carbonhydrates + Oxygen

Photosynthesis is the process through which plants prepare their food.

Answer 2

Synthesis of food in green plants takes place by chemical reaction in the plants which involves water, carbon dioxide , chlorophyll and ion presence of sunlight. The chemical reaction takes place in the leaves of the plant.