Question

in nature, during a 24 - hour period, what gas do green plants continuously use?
a. both carbon dioxide and nitrogen
b. oxygen, only
c. carbon dioxide, only
d. both carbon dioxide and oxygen

Explanation:

Green plants carry out photosynthesis (using carbon dioxide) during the day when there is light and cellular respiration (using oxygen) all the time (both day and night). Nitrogen is not directly used as a gas in these continuous processes relevant to the question.

Answer:

D. both carbon dioxide and oxygen