Note from The Future: please mentally replace all mentions of “gender” with “sex”.
Doc: With a sample of Heinkel’s blood and my brilliant accelerated growth method…I will solve the mystery of his/her gender once and for all!
Ta-da!
…
Rip: Hey, Doc, my alarm clock is–
[BOOM]
Major? Doc just blew up the lab. Yes, again.
Doc: Mine eyes have seen the glory…
Major: But why didn’t you look at the chromosomes?
Doc: If I did things the easy way, I wouldn’t be a mad scientist!