Similarly, when {HEAD ~ the pH} of the environment falls below {TAIL ~ the pH} of the protein, the protein has a net positive charge 
falls below
Similarly , when { HEAD ~ the pH } of the environment falls below { TAIL ~ the pH } of the protein , the protein has a net positive charge
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH