1. Non-polar amino acids. 10 (alanine, valine, glycine, proline, leucine, isoleucine, methionine,
Tryptrophin and phenylalanine.
2. Polar un-charged amino acids. 5 (serine, threonine).
3. Polar positively charged amino acids. 3 (lysine, histidine).
4. Polar negatively charged amino acids. 2 (glutamic)