# Selective breeding and chemical fertilisers are two methods used to increase food supply. Describe how each method increases the yield of a crop.

> Cambridge International IGCSE Biology (0610) — 20.1 Food supply · Describe · 4 marks

## Mark scheme (4 marks)

1. Selective breeding — organisms with desirable characteristics (e.g. high yield) are chosen to breed
2. Selective breeding — offspring inherit desirable characteristics / high yield, producing a large number of high-yielding plants
3. Chemical fertilisers provide / increase mineral salts / nutrients in the soil
4. Chemical fertilisers allow plants to grow larger / produce more fruit, increasing yield

## Key terms

- [selective breeding](https://www.gradenine.co.uk/glossary/selective-breeding)
- [chemical fertilisers](https://www.gradenine.co.uk/glossary/chemical-fertilisers)
- [yield](https://www.gradenine.co.uk/glossary/yield)

## 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/selective-breeding-and-chemical-fertilisers-are-cb76edfb) · Published by Druglandscape Ltd.