# Rubber is a natural polymer produced by some plants. A student claims that rubber must be built from repeating monomer units joined together. Explain what is meant by the terms monomer and polymer, and describe the type of chemical reaction that joins monomers together to form a polymer. Give one example of a monomer and its corresponding polymer found in the human body.

> AQA A-Level Biology (7402) — 3.1.1 Monomers and Polymers · Explain · 5 marks

## Mark scheme (5 marks)

1. A monomer is a small / single molecule that is the repeating unit / building block of a polymer
2. A polymer is a large molecule made from many monomers joined together
3. Monomers are joined together by condensation reactions
4. Water is released / produced during the condensation reaction
5. Correct named example: amino acid (monomer) and protein (polymer) OR glucose (monomer) and glycogen / starch / cellulose (polymer) OR nucleotide (monomer) and DNA / RNA (polymer)

## Key terms

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

## Related

- [Revision notes for AQA A-Level Biology (7402)](https://www.gradenine.co.uk/learn)
- [How to answer "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/rubber-is-a-natural-polymer-produced-cd241b2f) · Published by Druglandscape Ltd.