Stomata

The idea

Stomata are tiny pores on the surface of leaves that help in the exchange of carbon dioxide and oxygen during photosynthesis and respiration.

Gases in and out

A leaf takes in carbon dioxide and gives out oxygen. But the leaf has no mouth.

How do the gases pass in and out of a leaf?

• Through tiny pores on the leaf surface
• Only through the roots
• Through the flowers

Zoom into the leaf

Zoom into the surface of the leaf. Then look at photosynthesis and at respiration.

Stomata

The tiny pores are called stomata. Gases pass through them in both directions.

Stomata are tiny pores on the surface of leaves that help in the exchange of carbon dioxide and oxygen during photosynthesis and respiration.

• Process | Goes in | Comes out
• Photosynthesis | Carbon dioxide | Oxygen
• Respiration | Oxygen | Carbon dioxide

Notes

Stomata are tiny pores on the surface of leaves that help in the exchange of carbon dioxide and oxygen during photosynthesis and respiration.

Check yourself

What are stomata?

In photosynthesis, which gas goes in through the stomata?

In respiration, which gas goes in through the stomata?

Stomata help in the exchange of gases during …

• Tiny pores on the surface of leaves — correct. Yes! Gases pass through them.
• Tiny roots in the soil. Stomata are on the leaf surface, not in the soil.
• A kind of starch. Starch is stored food. Stomata are tiny pores.
• Oxygen. Oxygen is released in photosynthesis. Carbon dioxide goes in.
• Carbon dioxide — correct. Yes! The leaf takes it in from the air.
• Starch. Starch is not a gas. It is a food that the plant stores.
• Carbon dioxide. Carbon dioxide is released in respiration.
• Sunlight. Sunlight is not a gas. In respiration oxygen goes in.
• Oxygen — correct. Yes! Respiration uses oxygen.
• photosynthesis and respiration — correct. Yes! Both processes.
• only photosynthesis. They help in respiration too.
• only respiration. They help in photosynthesis too.