NEET BIOLOGY

PLANT PHYSIOLOGY

PHOTOSYNTHESIS

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
The role of the guard cell is to
A
help control the temperature of the plant
B
control how much water enters the leaf
C
control how much glucose is stored
D
control the movement of water vapour & gases
Explanation: 

Detailed explanation-1: -They help to regulate the rate of transpiration by opening and closing the stomata. Light is the main trigger for the opening or closing. Each guard cell has a relatively thick cuticle on the pore-side and a thin one opposite it.

Detailed explanation-2: -Guard cells are pairs of epidermal cells that control gas diffusion by regulating the opening and closure of stomatal pores.

Detailed explanation-3: -Guard cells use osmotic pressure to open and close stomata, allowing plants to regulate the amount of water and solutes within them. In order for plants to produce energy and maintain cellular function, their cells undergo the highly intricate process of photosynthesis .

Detailed explanation-4: -As the potassium ions accumulate in the guard cell, the osmotic pressure is lowered. A lower osmotic pressure attracts water to enter the cell. As water enters the guard cell, its hydrostatic pressure increases. The pressure causes the shape of the guard cells to change and a pore is formed, allowing gas exchange.

Detailed explanation-5: -The guard cells surround each stoma for their protection. They are the cells that regulate the rate of transpiration by opening and closing of stomata. The guard cells swells up and open the stomata for the exchange of gases when the plant has an excess of water.

There is 1 question to complete.