The term determinant is used here in a broad sense to denote that portion of {HEAD ~ the biological entity} involved in and responsible for {TAIL ~ selective binding} to a specific binding substance, the presence of which is required for selective binding to occur 
responsible for
The term determinant is used here in a broad sense to denote that portion of { HEAD ~ the biological entity } involved in and responsible for { TAIL ~ selective binding } to a specific binding substance , the presence of which is required for selective binding to occur
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD 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 OTH OTH OTH OTH OTH OTH