Death and Gender in Star Trek

This is something that I've become more aware of lately. In fiction, particularly heroic fiction, men die heroically saving the day, women die to make male characters angry and take appropriate action against the villain. Take Star Trek:

Spock: Died saving the Enterprise from Khan's Genesis Wave, Khan -> Alrdy defeated, Saved Kirk
Kirk: Died saving the universe from Soran, sacrifices his life to destroy the missile, killing Soran, Saved Picard
Tucker: Died saving Captain Archer, killed the bad ppls with him, Saved Archer
Data: Died saving the Enterprise from Shinzon's *sigh* 7-minute warning weapon, Shinzon -> Alrdy dead, Saved Picard

Yar: Died while walking, killed by Armas to show how ebil he is, Armas defeated by Picard
Dax: Died while praying, killed by Dukat to show how ebil he is and his fancy new powers, Dukat eventually defeated by Sisko

In the first 4 cases, not only do the characters die HEROICALLY, but their deaths SAVED THE DAY, and in fact SAVED THE MAIN CHARACTER, making their deaths mean THAT MUCH MORE

In the last 2 cases, they died to show off a villain's power and ebilness, and not actively doing nething to help. They didn't sacrifice their lives, and their deaths only served to motivate the main character to save the day.