# Describe how blood is an example of a tissue, and explain how blood vessels and the heart work together as part of an organ system.

> AQA GCSE Biology (8461) — 4.2.2 Animal tissues, organs and organ systems · Describe and Explain · 4 marks

## Mark scheme (4 marks)

1. Blood is a tissue because it is a group of cells with a similar structure and function
2. Blood contains red blood cells, white blood cells, platelets and plasma
3. Blood vessels and the heart are organs that work together / are grouped together to form an organ system
4. The heart pumps blood around the body / the organ system carries out the function of transporting substances around the body

## Key terms

- [tissue](https://www.gradenine.co.uk/glossary/tissue)
- [organ](https://www.gradenine.co.uk/glossary/organ)
- [organ system](https://www.gradenine.co.uk/glossary/organ-system)
- [blood](https://www.gradenine.co.uk/glossary/blood)

## Related

- [Revision notes for AQA GCSE Biology (8461)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe and 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-how-blood-is-an-example-c9a96350) · Published by Druglandscape Ltd.