Moderate

Opening and closing of stomata is due to the:

Correct answer: B. Change in turgor pressure of guard cells

  • A. Hormonal change in guard cells
  • B. Change in turgor pressure of guard cells
  • C. Gaseous exchange
  • D. Respiration

Explanation

It is turgor pressure in guard cells which determines the opening and closing of stomata. When the guard cells are swelled because of water absorption, it leads to opening of the stomatal pores. Once the water is lost, the guard cells become flaccid and the stomata closes. Also, during the daytime stomata generally remain open and during the night they remain closed. So correct option is B.

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