Xylem and phloem in roots, stems and leavesSpec 8.1.2
In short
Xylem and phloem are found together in vascular bundles in the roots, stems and leaves of a dicotyledonous plant. In the root, xylem is in the centre, often in an X shape, with phloem between its arms. In the stem, bundles form a ring with xylem inside and phloem outside. In a leaf vein, xylem lies above phloem.
You must be able to find xylem and phloem in sections of the roots, stems and leaves of a non-woody dicotyledonous plant. In all three organs they are found together, in groups called vascular bundles (veins in the leaf).
| Organ | Where the vascular tissue is | Xylem and phloem |
|---|---|---|
| Root | in the centre of the root | xylem in the middle, often in an X or star shape, with phloem between the arms of the X |
| Stem | vascular bundles in a ring near the outside of the stem | in each bundle, xylem is on the inside and phloem on the outside |
| Leaf | in the midrib and the veins | in each vein, xylem is on the upper side and phloem on the lower side |
To identify the tissues in a photograph, find the vascular bundle or vein first, then use its position to decide which tissue is which.
Do not mix up the order in the stem. Phloem is on the outside of each bundle and xylem is on the inside.
Quick check
What does phloem transport?
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Sucrose and amino acids.
What are the two functions of xylem?
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Transport of water and mineral ions, and support.
In a stem, which tissue is on the outside of a vascular bundle?
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Phloem.
Supplement Why do xylem vessels have no cross walls?
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The cells are joined end to end to make a long continuous tube.
Written and checked against the Cambridge IGCSE Biology (0610) specification · Updated October 2026