The main functions of the stem are to provide support for plant leaves, transport minerals and water from the soil and carry sugar or glucose made in the leaves to other plant parts. Plants can have herbaceous or woody stems.
Herbaceous stems are typically green and pliable, while woody stems have an outer covering called bark. Another difference is that a herbaceous stem has notch-like structures for leaf development, and a woody stem has small apertures that are necessary for transpiration.
Plants also consist of other important parts, such as the roots, leaves, flowers and seeds. Photosynthesis takes place in the leaves, while the roots remain underground and take in water and nutrients from the soil.