{HEAD ~ The linking groups} provide {TAIL ~ adequate distance} between the dye and the biomolecule for efficient attachment without imparting excessive hydrophobicity 
provide
{ HEAD ~ The linking groups } provide { TAIL ~ adequate distance } between the dye and the biomolecule for efficient attachment without imparting excessive hydrophobicity
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH