Which one of the following ions plays a critical role in the opening and closing of stomata?

Question

Quizplus · Accepted Answer

Potassium ions play a critical role in the opening and closing of stomata by regulating the water balance of guard cells. When K⁺ ions enter the guard cells, water follows by osmosis, causing the cells to swell and the stomata to open. When K⁺ ions leave the guard cells, water also leaves, causing the cells to shrink and the stomata to close.

Which One of the Following Ions Plays a Critical Role