sentences:  First, a waterproof outer covering or cuticle evolved that reduced water loss.Secondly, variable apertures, the  stomata that could open and close to regulate the amount of water lost by evaporation during uptake and thirdly intercellular space between photosynthetic parenchyma cells that allowed improved internal distribution of the to the chloroplasts.This three-part system provided improved homoiohydry, the regulation of water content of the tissues, providing a particular advantage when water supply is not constant.