Question

Opening and closing of stomata is controlled by

• A. $K^{+}$
• B. $M{g}^{2+}$
• C. $C{a}^{2+}$
• D. None of the above

Answer 1

The correct option is A $K^{+}$

Potassium ions are involved in turgor movement of guard cells. Formation of organic acids like malic acid in guard cells promotes intake of potassium into the guard cells, which causes a decrease in water potential leading to intake of water by guard cells.