How is the division of the shoot into stem and leaves related to the performance of its functions?

Any higher plant has two parts, it is underground or root and aboveground (shoot). The shoot, in turn, also includes organs such as the stem and leaves. Each of the above-named parts of the plant performs its own function. For example, the stem serves as a conduit for nutrients and water from roots to leaves and vice versa. It also performs support and storage functions. It is a vegetative reproductive organ. The most important function of the leaves is photosynthesis and the evaporation of excess water.