In guard cells when sugar is converted into starch, the stomatal pore

Options

A. Opens fully
B. Opens partially
C. Closes completely
D. Remains unchanged

Answer

C

Explanation

In dark the level of respiratory `CO_(2)` is increased and thus decreases in pH . At low pH the glucose molecule is converted to glucose I phosphate making use of respiratory ATP and then they are converted to starch in the presence of enzyme phosphorylase. Thus OP of cell sap is decreased and water potential is increased and the guard cells lose water and stomatal pore is closed.