Wilting of leaves in hot weather is due to

During stomatal opening (photoactive),which of the following does not occur?

When does the stomatal aperture open?

Identify $X$ and $Y$ from the figure.

Arrange the events of opening stomata in correct sequence and choose the correct option accordingly.
$I.$ Lowering of osmotic potential of guard cells
$II.$ Decline in guard cell solute
$III.$ Rise of potassium ion level in guard cells
$IV.$ Guard cells absorb water from neighbouring epidermal cells
$V.$ Guard cells become flaccid
$VI.$ Guard cells swell and create a pore between them

Wilting of a plant results from excessive