# Describe how predation affects the size of a prey population, and explain what happens to the predator population as a result of changes in prey numbers.

> Cambridge International IGCSE Biology (0610) — 19.4 Populations · Describe · 4 marks

## Mark scheme (4 marks)

1. When predator numbers increase, prey population size decreases
2. A decrease in prey numbers leads to a decrease in food supply for predators, causing the predator population to decrease
3. A decrease in predator numbers allows the prey population to recover / increase
4. The predator and prey populations cycle / fluctuate in a linked / interdependent way, with predator numbers peaking after prey numbers peak

## Key terms

- [population](https://www.gradenine.co.uk/glossary/population)
- [predator](https://www.gradenine.co.uk/glossary/predator)
- [prey](https://www.gradenine.co.uk/glossary/prey)

## Related

- [Revision notes for Cambridge International IGCSE Biology (0610)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

---
Source: [GradeNine](https://www.gradenine.co.uk/q/describe-how-predation-affects-the-size-1d20fe55) · Published by Druglandscape Ltd.