Such changes may be {TAIL ~ the result} of {HEAD ~ exposure} of the cells to environmental toxins 
Such changes may be { TAIL ~ the result } of { HEAD ~ exposure } of the cells to environmental toxins
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH