# Describe the importance of biodiversity and explain how human activities can reduce it.

> Edexcel A-Level Biology A: Salters-Nuffield (9BN0) — 2.5 Biodiversity · Describe / Explain · 5 marks

> Tropical rainforests contain millions of species of organisms. In recent decades, large areas of rainforest have been cleared to make way for agriculture and urban development.

## Mark scheme (5 marks)

1. Biodiversity refers to the variety of different species found in an area / on Earth
2. High biodiversity is important for ecosystem stability / resilience, so that if one species declines the ecosystem can continue to function
3. High biodiversity provides resources for medicine / food / raw materials that benefit humans
4. Deforestation / clearing land for agriculture removes habitats, reducing the number of species that can live there
5. Other human activities such as pollution, over-hunting / over-fishing, or introduction of invasive species also reduce biodiversity by decreasing species numbers

## Key terms

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

## Related

- [Revision notes for Edexcel A-Level Biology A: Salters-Nuffield (9BN0)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe / 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/describe-the-importance-of-biodiversity-and-8dd2b575) · Published by Druglandscape Ltd.