When {TAIL ~ the pH} rises above the pI of the protein, the protein assumes {HEAD ~ a net negative charge} 
When
When { TAIL ~ the pH } rises above the pI of the protein , the protein assumes { HEAD ~ a net negative charge }
REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD