Question

“All plants give out oxygen during the day and carbon dioxide during the night”. Do you agree with this statement? Give reason.

Answer 1

Exchange of gases in plants:

1. The above statement is assumed and not true.
2. Plants release oxygen when they perform photosynthesis.
3. During this process, they use up carbon dioxide.
4. Since photosynthesis requires sunlight, it occurs only in the daytime, which thus means that plants give out oxygen during the day.
5. Plants give out carbon dioxide during respiration, which takes place during the day as well as at night.
6. Thus, carbon dioxide is released by plants throughout the day except during photosynthesis, where it is used to make food.
7. Since photosynthesis does not occur at night, the amount of carbon dioxide released seems higher.