The form and structure of tropical rain forest plants do not permit them to live in the desert, just as the cacti and succulents of the desert will not thrive in the rain forest. The structure, form and life cycles of plants are attuned to specific combinations of environmental factors. This gives rise to the rich diversity of leaf forms and specializations. There are plants whose leaves are partly or completely modified as tendrils . These leaves, when curled tightly around rigid objects, help the plant in climbing or in supporting weak stems as in garden peas.
Many desert plants have their leaves modified as spines .
This exposed end is covered with a thick epidermis and cuticle. It has few pores or stomata and is relatively transparent. Specialized leaves known as bracts are found at the bases of flowers or flower stalks. Such plants grow mainly in swampy areas and bogs of tropical and temperate regions. In such environments certain elements may be deficient in the soil, or they may not be readily available to the plants.