# Explain why plants need both xylem and phloem vessels, referring to the substances transported in each.

> WJEC GCSE Biology (Wales) — 1.5.1 Plant structure and function · Explain · 4 marks

## Mark scheme (4 marks)

1. Xylem transports water (and mineral ions) from roots to leaves/shoots
2. Water transported by xylem is needed for photosynthesis (and to keep cells turgid)
3. Phloem transports sugars/glucose (dissolved food) made in leaves to other parts of the plant
4. Sugars transported by phloem are needed for respiration or growth in non-photosynthesising parts (e.g. roots, growing tips, storage organs)

## Key terms

- [xylem](https://www.gradenine.co.uk/glossary/xylem)
- [phloem](https://www.gradenine.co.uk/glossary/phloem)
- [transport](https://www.gradenine.co.uk/glossary/transport)

## Related

- [Revision notes for WJEC GCSE Biology (Wales)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/explain-why-plants-need-both-xylem-bca23965) · Published by Druglandscape Ltd.