# Proteins can be broken down into their amino acid building blocks. Describe how proteins are digested in the human body, and explain why the amino acids produced are important.

> WJEC A-Level Chemistry (Wales) — 4.7 Amino acids, peptides and proteins · Describe and Explain · 5 marks

## Mark scheme (5 marks)

1. Proteins are broken down / hydrolysed by enzymes (proteases / digestive enzymes)
2. The peptide bonds between amino acids are broken during digestion
3. Digestion produces individual amino acids (the monomers)
4. Amino acids are small enough to be absorbed into the bloodstream / through the gut wall
5. Amino acids are used to make new proteins needed by the body (e.g. for growth / repair / making enzymes / structural proteins)

## Key terms

- [protein](https://www.gradenine.co.uk/glossary/protein)
- [amino acid](https://www.gradenine.co.uk/glossary/amino-acid)

## Related

- [Revision notes for WJEC A-Level Chemistry (Wales)](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/proteins-can-be-broken-down-into-e2f4ffe8) · Published by Druglandscape Ltd.