Proteins are polymers of amino acids. There are 20 different amino acids which vary from each other by having different types of R groups. The simplest R group is H (hydrogen) which is found on the amino acid called Glycine
A) acid group
B) Amino group
Glycine is insoluble. For an amino acid to be soluble it has to have an ion.
Different R groups can be more complex, and they give amino acid slightly different properties.
