Question

Stomata generally operate in response to ________________.

• A. Atmospheric humidity
• B. Soil temperature
• C. Atmospheric temperature
• D. Light

Answer 1

Answer: (D)

Light

Stomata are tiny pores confined to epidermis of the leaves which grants in gas exchange. Here, the water vapour leaves the plant and carbon-di-oxide enters. Each stomata is surrounded by specialized cell called guard cells, which are kidney-bean shaped. These are the cells helps to regulate transpiration by opening and closing of stomata. In the presence of light, guard cells take up water by osmosis and it become turgid so that carbon dioxide is available for the light-dependent process of photosynthesis. Whereas, in darkness water is lost and thus pores get closed.
So, the correct option is D.