# Describe the role of producers in a food chain and explain what happens to the amount of biomass available as energy is transferred through successive trophic levels.

> Pearson Edexcel International GCSE Biology (4BI1) — 4.2 Feeding relationships · Describe · 4 marks

> In a pond ecosystem, microscopic algae are eaten by water fleas, which are eaten by small fish, which are in turn eaten by pike.

## Mark scheme (4 marks)

1. Producers (algae) are photosynthetic organisms that make/produce biomass / organic matter using light energy
2. Only around 10% of the energy / biomass is transferred from one trophic level to the next
3. Energy / biomass is lost through respiration (heat release) at each trophic level
4. Therefore the biomass available decreases / gets smaller at each successive trophic level, forming a pyramid of biomass shape

## Key terms

- [producer](https://www.gradenine.co.uk/glossary/producer)
- [trophic level](https://www.gradenine.co.uk/glossary/trophic-level)
- [biomass](https://www.gradenine.co.uk/glossary/biomass)
- [food chain](https://www.gradenine.co.uk/glossary/food-chain)

## Related

- [Revision notes for Pearson Edexcel International GCSE Biology (4BI1)](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)

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Source: [GradeNine](https://www.gradenine.co.uk/q/describe-the-role-of-producers-in-3422a070) · Published by Druglandscape Ltd.