# A population of aphids (small insects) reproduces asexually during summer when food is plentiful, but switches to sexual reproduction in autumn when conditions become harsh. Explain why asexual reproduction is beneficial during summer but why the population is at risk if it relies only on asexual reproduction.

> Cambridge International IGCSE Biology (0610) — 16.1 Asexual reproduction · Explain · 4 marks

## Mark scheme (4 marks)

1. Asexual reproduction allows rapid production of large numbers of offspring, which is beneficial when conditions are favourable
2. Asexual reproduction takes less energy / is more efficient than sexual reproduction
3. All offspring are genetically identical / clones, so a single pathogen or disease can destroy the entire population
4. Genetically identical offspring cannot adapt to environmental changes, so if conditions become harsh the population may not survive

## Key terms

- [asexual reproduction](https://www.gradenine.co.uk/glossary/asexual-reproduction)

## Related

- [Revision notes for Cambridge International IGCSE Biology (0610)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
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Source: [GradeNine](https://www.gradenine.co.uk/q/a-population-of-aphids-small-insects-67ef97d9) · Published by Druglandscape Ltd.