Question

In guard cells, during day there is

• A. efflux of
• B. influx of
• C. uptake of
• D. all of these

Answer 1

The correct option is D all of these

During the presence of sunlight, starch is converted into malic acid in guard cells, which dissociates into malate ions and protons. The protons are pumped out in exchange of $K^{+}$ ions from surrounding cells. Some $C{l}^{-}$ ions enter the guard cells too. This leads to the opening of stomata.