Guard cells are located on the surface of the underside of leaves. how does this structure of the leaf enable the function of guard cells?

Basically, guard cells are cells surrounding each stoma and they help to set the rate of transpiration by opening and closing the stomata. Some guard cells are turgid or swollen and the stomatal opening is large. Hence ths turgidity is caused by the accumulation of the potassium ions in the guard cells. Thus, when the potassium ions or K+ levels happen to increase in the guard cells the water potential of the guard cells drops and water enters the guard cells. Some guard cells have lost water which causes the cells to become flaccid and the stomatal opening to close. This may occur when the plant has lost an exessive amount of water. Moreover guard cells function are the stomatal closing and the stomatal opening of the plant.

if you add everything up correctly you should get 69 i got this because 50 plus 19 is it