Page 7 - ACTIVE SCIENCE 4 TOC

LET’S
REVISE

• Leaves have various shapes and sizes.
• They are the food manufacturers of the plants.

• The flat part of the leaf is called blade or lamina.
• The leaf has a main vein called the midrib.

• The exchange of oxygen and carbon dioxide takes place through the stomata.
• Inter-relationship between plants and animals helps to keep balance in nature.

Glossary
• Photosynthesis : Photosynthesis is the process through which plants use

water, sunlight and carbon dioxide to make their food and
release oxygen in the air.

• Cuticle : The protective outer waxy coating of the leaf.
• Petiole : The stalk by which a leaf is attached to the stem.

• Stomata : Tiny openings on the leaf for the exchange of gases.

• Chlorophyll : The green pigment in the leaves which gives green colour to
the leaves.

• Food chain : A chain that shows the dependance of food of one organism
on another.

Practice Time

A. Tick the correct option.

1. The plants take carbon dioxide from the atmosphere through _____________.
a. roots b. stems

c. flowers d. leaves
2. Which part of the plant takes in carbon dioxide from air for photosynthesis?

a. Vein of a leaf b. Stomata

c. Roots d. Sepals
3. The food in plants, is stored as _____________.

a. starch b. chlorophyll
c. oxygen d. stomata

14 Active Science-4