The main function of xylem cells is to carry water and soluble minerals from the root to the leaves of a plant. However, a secondary function of xylem tissue is to provide support for the plant. Xylem is present in vascular plants and is made up of different types cells, such as tracheids, fibers and parenchyma.
Xylem is found in the wood of trees. As the tree grows, there are two different types of xylem formed, which are primary and secondary xylem. In old trees, secondary xylem is found on its outer layer. When trees are cut down, the exposed tree rings are old or dead xylem tissue, which is the primary xylem.