{HEAD ~ Proteins} are comprised of {TAIL ~ amino acids}, which are ambivalent their charge changes based on the pH of the environment to which they are exposed 
are comprised of
{ HEAD ~ Proteins } are comprised of { TAIL ~ amino acids } , which are ambivalent their charge changes based on the pH of the environment to which they are exposed
HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH