In a microbial fuel cell, {HEAD ~ the transgenic microbes} have {TAIL ~ access} to a feedstock 
have
In a microbial fuel cell , { HEAD ~ the transgenic microbes } have { TAIL ~ access } to a feedstock
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH