Question

Explain the process of production of food in plants.

Answer 1

Hint: The green plants have an autotrophic means of nutrition. ‘Auto’ means ‘self’ and ‘troph’ means ‘nutrition’. Thus, autotrophic means ‘self-nutrition’.

Complete Answer-
Like other organisms, plants also require food which can supply energy for their metabolic activities.
Green plants make their own food by the procedure of photosynthesis. ‘Photo’ means ‘light’ and ‘synthesis’ means ‘to build’.
Food is made in the green leaves of the plants by combining $CO_2$ and Water in the presence of sunlight and chlorophyll. The $CO_2$ required for making food is taken by the plant leaves from the air.
Then, $CO_2$ enters the leaves through tiny pores called stomata.
Water required for creating food is taken from the soil. Then, the water is transported to the leaves from the soil through roots and stems.
The sunlight provides energy required to hold out the reaction involved within the preparation of food.
The green colour pigment called chlorophyll is present in the green leaves that helps to absorb the energy from sunlight.
$O_2$ gas is produced as a by-product during the preparation of food and goes into the air.
The food prepared by the green leaves is in the form of simple sugar called glucose that is sent to the other parts of the plant.
Extra glucose changed into another food called starch. This starch is stored in the leaves.

NOTE-
Green plants convert sunlight energy into chemical energy by making carbohydrates (foods). This food provides all the energy to the plant.
There are 3 steps in photosynthesis:
1. Absorption of sunlight by chlorophyll.
2. Convert light energy to chemical energy and splitting of water into Hydrogen and Oxygen by light energy.
3. Reduction of $CO_2$ by hydrogen to form glucose by utilizing the chemical energy.
The 3 steps involved in photosynthesis need not take place one after the other immediately. They can take place at different times.