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