Question

Guard cells fully close the stomatal pore only when water is freely available.

• A. True.
• B. False.

Answer 1

The correct option is B

False.

The guard cells regulate the opening and closing of stomata. The stomatal pore is wide open when water is freely available during which the guard cells become turgid and closed when water availability is critically low during which the guard cells become flaccid. This is because when water is freely available, it can afford to lose some water through transpiration as it opens stomata for gaseous exchange, whereas when water is critically low, it closes the stomata to prevent water loss.