AP BIOLOGY

Detailed explanation-1: -So, plants take in carbon dioxide from the atmosphere for preparing food. At night, photosynthesis does not occur hence they take in oxygen and give out carbon dioxide. Therefore, it is said that during the daytime, plants take in carbon dioxide and give out oxygen, and during the night it is vice-versa.

Detailed explanation-2: -During photosynthesis, plants take in carbon dioxide (CO2) and water (H2O) from the air and soil. Within the plant cell, the water is oxidized, meaning it loses electrons, while the carbon dioxide is reduced, meaning it gains electrons. This transforms the water into oxygen and the carbon dioxide into glucose.

Detailed explanation-3: -Plants release oxygen during the day in the presence of natural light through the process of photosynthesis. While at night, the plants uptake oxygen and release carbon dioxide, which is called respiration.

Detailed explanation-4: -Leaves. The exchange of oxygen and carbon dioxide in the leaf (as well as the loss of water vapor in transpiration) occurs through pores called stomata (singular = stoma). Normally stomata open when the light strikes the leaf in the morning and close during the night.

Detailed explanation-5: -This is an incorrect statement. All plants carry on respiration throughout 24 hours and thus give out carbon dioxide during the day as well as night. But photosynthesis happens only in presence of sunlight and so oxygen is released during daytime.