Grr. My comment on this seems to have not been posted.
Anyway, zentran:zentraedai::human:humanity is I guess the best way to explain it. If I remember correctly, in Macross zentraedai referred specifically to the male of the species, females were meltrandi.
Anyway, the race as a whole was bioengineered to be a tough warrior species, so they can survive in vacuum just by keeping their mouths closed. Since she's quarter-zentran, her eardrums didn't explode from the lack of pressure.
Anyone else notice the number of refs to the original they're jamming in? I fully expect next episode to involve Mikhail and Klan Klein playing videogames against each other.