Nutrition in plants for class 7 worksheet with answers

Why do organisms necessary to take food?

Food is necessary by all organisms for many purposes.

(a) Food helps in the growth and development of the body.

(b) Food gives us energy for movement such as running, walking kicking, etc.

(c) It is also needed for replacement and repairing damaged parts of the body.

(d) It gives us resistance to fight against diseases and prevents us from infections.

Distinguish between parasite and saprophyte


The parasite lives on a living organism.

It lives on a living source known as the host for its nutritional requirements.


Saprophyte lives on the dead and decaying matter for their nutritional requirements.

How would we test the presence of starch in leaves?

We can test the presence of starch in leaves with an iodine test. When we remove chlorophyll from the leaf by boiling it in alcohol and then putting 2 drops of iodine solution, its color change to blue indicates the presence of starch.

Give a brief description of the process of synthesis of food in green plants.

Green plants have chlorophyll in the leaves. The leaves use carbon dioxide and water to prepare food in presence of. sunlight.

CO2 +H2O —– Glucose +oxygen