Xylem and phloem
Section: Biology | Syllabus: Cambridge IGCSE Combined Science (0653)
Functions of Xylem and Phloem
Plants have two types of vascular (transport) tissue that run throughout the plant body, together forming the vascular bundles seen in roots, stems and leaves.
- Xylem transports water and mineral ions, and also provides structural support
- Phloem transports sucrose and amino acids
Position of Xylem and Phloem
The position of xylem and phloem can be identified in cross-sections of the root, stem and leaf of a non-woody dicotyledonous plant:
| Part of plant | Position of xylem | Position of phloem |
|---|---|---|
| Root | Central core, forming an X-shape (star-shaped) in the centre | Between the arms of the xylem star |
| Stem | In vascular bundles arranged in a ring near the outer edge; xylem is on the inner side of each bundle | On the outer side of each vascular bundle, facing the epidermis |
| Leaf (midrib/vein) | Upper side of the vein | Lower side of the vein |
The arrangement of xylem and phloem differs between the root, stem and leaf
Interactive revision notes, videos and practice questions load below.