Question

How is the stomata formed?

Answer 1

The guard cells are produced in pairs with a gap between them that forms a stomal pore.
Opening and closure of the stomatal pore is mediated by changes in the turgor pressure of the two guard cells. When turgor pressure increases, guard cells swell and the stomatal pores open. In addition, guard cells take up sugars that also contribute to opening of the stomatal pores.