CBSE Class 4 Science Food for plants

I DEFINE – KEYWORDS (PAGE 10)

II ANSWER THE FOLLOWING QUESTION

1. What happens to the food prepared in the leaves?

Ans. The food produced by the plants is in the form of sugar and the extra sugar produced is changed to starch and is stored in different parts of the plant such as in roots, stems, leaves, fruits and flowers.

2. Describe the process of photosynthesis.

Ans. The process by which green plants produce food using carbon-di-oxide, water and chlorophyll in the presence of sun light is called photosynthesis.

3. Why should we grow plants near our houses?

Ans. Plants produce oxygen as a waste product during photosynthesis. We humans breathe in oxygen. Hence, we should grow plants and trees near our house.

4. Write a paragraph describing how preparing food by plant is similar to cooking food.

Ans. As food is prepared in the kitchen of a house, so is the food prepared in the leaves of a plant using carbon-di-oxide, water and chlorophyll in the presence of sun light.

5. Describe an experiment to test for starch in a leave.

Ans. Aim – to test the presence of starch.

I. Take a leaf from a potted plant.

II. Boil the leaf in water for 10 Minutes.

III. Dip the leaf in warm alcohol.

IV. Add a few drops of Iodine on the leaf.

V. The leaf turns bluish black, showing the presence of starch.