# Explain why plants need both xylem and phloem vessels, and describe how each vessel is adapted for its function.

> Eduqas A-Level Biology — 2.1 Classification and biodiversity · Explain · 5 marks

## Mark scheme (5 marks)

1. Xylem transports water (through the plant from the roots) / water is needed for photosynthesis or other cellular reactions
2. Phloem transports sugars / food nutrients (up and down the plant) in translocation
3. Xylem is made from hollowed-out dead cells with ends removed, forming a continuous tube for water to pass through
4. Xylem cells are impermeable to water (so water stays in the vessel and is not lost through the walls)
5. Phloem is made of living cells / companion cells provide energy for transport of sugars

## Key terms

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

## Related

- [Revision notes for Eduqas A-Level Biology](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-453d9d42) · Published by Druglandscape Ltd.