We will learn about the identification of a stem and how to differentiate a stem from root.
We have already learned that plants have two distinct parts; one grows underground and the other above ground. The underground part is the root and the other portion of a flowering plant is the shoot, which remains above ground. The shoot system of a flowering plant is composed of stem, leaves, buds, flowers and fruits.
Definition of a stem: The portion of the vascular plant, which grows towards light and holds the leaves, flowers and fruits is known as stem.
The central axis of the shoot system is called the stem. It is a rod shaped structure. At regular intervals it has slightly swollen regions, called nodes, which gives rise to leaves. Each portion in between two nodes is called internode. At the junction of a leaf and a node, a tiny outgrowth is present; it is called axillary bud. At the tip of the main stem a bud is found, which is called the apical bud.
Axillary buds grow to form branches. The branches are thinner than the main stem but they also bear similar nodes and internodes.
Some buds modify itself to grow into flowers. Flowers are the reproductive shoots of a plant. Flowers transform into fruits. These fruits bear seeds and when the seeds come on soil they germinate (initial phase in the development of a seed) and grow into baby plants.