Under {HEAD ~ these conditions cells} extend neurites, develop {TAIL ~ electrical excitability} and express genes encoding neuronal cell specific proteins  
develop
Under { HEAD ~ these conditions cells } extend neurites , develop { TAIL ~ electrical excitability } and express genes encoding neuronal cell specific proteins
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH