{HEAD ~ The dendritic structures} comprise {TAIL ~ linkers} and branch groups covalently bonded to each other in any of various structural combinations 
{ HEAD ~ The dendritic structures } comprise { TAIL ~ linkers } and branch groups covalently bonded to each other in any of various structural combinations
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH