. "\"The process in which a cell in an open tracheal system becomes capable of differentiating autonomously into a terminal cell in an environment that is neutral with respect to the developmental pathway; upon specification, the cell fate can be reversed. Terminal cells send long and bifurcated hollow branches toward target tissues to allow oxygen exchange.\" [GOC:mtg_sensu, PMID:10684581, PMID:11063940]" . . "terminal cell fate specification, open tracheal system" . "terminal cell fate specification" . .