# Explain why active transport stops when a cell is deprived of oxygen.

> Cambridge International IGCSE Biology (0610) — 3.3 Active transport · Explain · 4 marks

> Root hair cells actively transport nitrate ions from the soil into the cell against the concentration gradient. A student noticed that when the roots of a plant were waterlogged and deprived of oxygen, the uptake of nitrate ions stopped.

## Mark scheme (4 marks)

1. Active transport requires energy from respiration
2. Oxygen is needed for (aerobic) respiration
3. Without oxygen, (aerobic) respiration stops / is reduced, so less / no energy is produced
4. Without energy, carrier proteins cannot change shape / cannot move nitrate ions against the concentration gradient

## Key terms

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

## Related

- [Revision notes for Cambridge International IGCSE Biology (0610)](https://www.gradenine.co.uk/learn)
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Source: [GradeNine](https://www.gradenine.co.uk/q/explain-why-active-transport-stops-when-6c12b0f2) · Published by Druglandscape Ltd.