Question

The opening and closing of the stomatal pore depends upon

• A. oxygen
• B. temperature
• C. water in guard cells
• D. concentration of carbon dioxide in stomata

Answer 1

The correct option is C

water in guard cells

The correct option is C.

Explanation of the correct option:

• Stomata facilitate the exchange of oxygen and carbon dioxide between plants and the environment.
• Stomata are composed of two guard cells. Whenever the turgor pressure inside the guard cells increases, the stomatal pore opens but on the other hand, when the turgor pressure decreases stomatal pore starts to close.
• Turgor pressure inside the guard cells is created due to the osmotic flow of water inside the guard cells.

Explanation of the incorrect options:

Option A:

• Oxygen is released during the process of photosynthesis when carbon dioxide and water combine together in the presence of sunlight.

Option B:

• Optimum temperature is essential for the growth of plants.

Option D:

• Stomata facilitate the entry of carbon dioxide inside plant cells during the process of photosynthesis.

Therefore, the opening and shutting of the stomatal pore depend upon the water in the guard cells.