The body of a land plant is composed of a shoot system and a root system. The shoot includes the stem, leaves, and other reproductive systems. The stem is the axis or supporting column of the shoot system, providing support for the leaves and the reproductive structures. It is the channel through which water and mineral elements derived from the soil flow from the roots to the upper parts of the plant. It is also the route taken by organic products synthesized in the leaves when they are transported to other plant parts.

Anatomy

The structure of the stem is organized around the vascular or conducting system, which in seed plants consists of an interconnected pattern of bundles extending lengthwise in the stem. At each node, or site of leaf attachment, one or more of the bundles bends outward into the petiole (leaf stalk) to provide the vascular...