The leaves of a desert plants often have two or more layers of palisade mesophyll, rather than the single layer that is a characteristic of most leaves. how might this modified structure be advantageous to a desert plant

PALISADE CELLS ARE CELLS FOUND WITHIN THE MESOPHYLL IN LEAVES OF DICOTYLED ON PLANTS.THEY CONTAIN CHLLORPLASTS,WHICH CONVERT THE ENERGY STORED IN PHOTONS TO CHEMICAL ENERGY THROUGH PHOTOSYNTHESSIS,WHICH IS MADE UP OF TWO MIN STAGES;THE LIGHT DEPENDENT REACTIONS AND LIGHT INDEPENT REACTIONS

Ithink that its like 15 mph.