Vascular tissue consists of xylem and phloem and evolved to transport water and nutrients in land plants. Xylem is composed of tracheids and vessel elements that form tubes to transport water and minerals from roots to leaves. Phloem is made of sieve tube cells and companion cells that transport sugar and nutrients in the opposite direction from leaves to other plant parts. Together, xylem and phloem allow for circulation of water, minerals and organic compounds throughout the plant.