# Explain the importance of inorganic ions in the synthesis of proteins and in the generation of electrochemical gradients across cell membranes.

> AQA A-Level Biology (7402) — 3.1.8 Inorganic Ions · Explain · 5 marks

## Mark scheme (5 marks)

1. Nitrate ions are needed for the synthesis of amino acids / proteins
2. Amino acids are the monomers / building blocks that are joined to form proteins
3. Sodium ions (or potassium ions) are involved in generating an electrochemical gradient across cell membranes
4. The electrochemical gradient results in a potential difference / voltage across the membrane
5. This electrochemical gradient / potential difference is important for processes such as nerve impulse transmission / active transport / ATP synthesis

## Key terms

- [inorganic ions](https://www.gradenine.co.uk/glossary/inorganic-ions)
- [electrochemical gradient](https://www.gradenine.co.uk/glossary/electrochemical-gradient)

## 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/explain-the-importance-of-inorganic-ions-af73b396) · Published by Druglandscape Ltd.