Question

When stomata closes which of the following events does not occur?

• A. Guard cell become flaccid
• B. Sugar is converted to starch
• C. O.P of the guard cell decreases
• D. Accumulation of $O_2$ takes place

Answer 1

The correct option is D Accumulation of $O_2$ takes place

According to the most accepted theory of stomatal opening and closing. The stomatal pore opens, when the guard cells become turgid and close when they become flaccid. The guard cells become turgid, when water gains entry into them as a result of increase in osmotic pressure, because of conversion of starch to sugar. These changes are reversed during closing of stomata. Accumulation of oxygen in guard cells is not related to opening and closing of stomata.