Question

ABA causes temporary closure of stomata when there is a shortage of water because it

• A. delays cell division & cell elongation
• B. interferes with the transport of $K^{+}$ ions into the guard cells
• C. causes rapid abscission of leaves & flowers
• D. it stops mitosis in vascular cambium during winter season

Answer 1

The correct option is B

interferes with the transport of $K^{+}$ ions into the guard cells

ABA changes the permeability of guard cells membrane thereby interfering with the transport of potassium ions. This results in the closure of the stomata when there is a shortage of water.