# DNA is a polymer made from nucleotide monomers. Describe the structure of DNA, including the type of polymerisation used to form it and the number of different monomers involved.

> AQA A-Level Chemistry (7405) — 3.3.13 Amino acids, proteins and DNA (A-Level only) · Describe · 5 marks

## Mark scheme (5 marks)

1. DNA is made from nucleotides (which are the monomers)
2. There are four different nucleotides
3. DNA is formed by condensation polymerisation
4. Small molecules (such as water) are lost / released during condensation polymerisation
5. Most DNA molecules consist of two polymer chains in the form of a double helix

## Key terms

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

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Source: [GradeNine](https://www.gradenine.co.uk/q/dna-is-a-polymer-made-from-a9668356) · Published by Druglandscape Ltd.