Question

Stomatal opening in plants occurs due to influx of:

• A. Na
• B. K
• C. ABA
• D. Auxins

Answer 1

Answer: (B)

K

Answer 2

It has been now experimentally proved that opening of stomata is an energy consuming process and not closing. The turgidity of guard cells is usually controalled by $K ^{+}, Cl ^{-}$ and $H ^{+}$. The opening of stomata is initiated by excretion of $H^{+}$by guard cells, intake of $K^{+}$and $C l^{-}$and closing is controlled by abscisic acid.