They are similar in three main ways
1.Both DNA and proteins are polymers.
- Both are made from smaller subunits joined together. DNA is made of subunits called nucleotides joined together and protein is made up subunits called amino acids joined together.
- In both of them, these subunits or monomers are linked together by covalent bonds.
Nucleotides are a combination of a nitrogen - rich base that is either adenine, guanine, cytosine or thymine, together with a phosphate group and a sugar.