The sizes of structures arranged from the smallest to the largest are:
1. C, H, O, N These are the individual atoms that make up the protein molecules and so they are the smallest units
2. Amino acid This is the primary structure of the protein molecule
3. Amino acid sequence This is the secondary structure of the protein molecule and contains many amino acids linked together in a specific order
4. Quaternary structure This is the largest of the given options and is actually the entire protein molecule and how this molecule shapes itself due to interactions between the amino acids present in the molecule
