Question

Answer the following in detail.

Explain the process of the exchange of gases in plants. 

Answer 1

In plants, the exchange of gases takes place through stomata and lenticels.

1. Stomata – They are tiny pores present on the lower surface of leaves and young green stems. The gaseous exchange takes place in plants mostly through stomata. They remain open during the day and close at night.
2. Lenticels – In certain trees, the mature roots and woody stems have tiny openings called lenticels which enable the oxygen to reach the intercellular spaces of interior tissues and carbon dioxide to be released into the atmosphere. The exchange of gases (oxygen and carbon dioxide) in plants takes place by two processes – photosynthesis and respiration

• Photosynthesis occurs during the day. It takes in carbon dioxide and gives out oxygen. A part of oxygen formed is used by plants for respiration and rest is given out through stomata
• Respiration occurs throughout day and night. Oxygen is used and carbon dioxide is given out. This carbon dioxide is used by the plant for photosynthesis during the day. At night, in the absence of photosynthesis, carbon dioxide is released into the air through stomata.