Bending Gender Abuses

So why is it that so many downright awful swear words and abuses/gaalis have gendered undertones..and often overtones? Why is there a gender bias even in absolute unimportant issues like abuses? Say for example...

son of a bitch - You're abusing the son...but then, why you need to go through his mother? why? whats the point??

Mother and Sisterfucker. again..the latter f-person is being attacked..with his mother and sister being invoked in the bargain. hmm. I wonder why?

Is it because women are the symbolic capital of the stereotypical family and attacking them gets through to the whole clan? Or is it because women have always been considered as private property of men, and not any individual identity at all! If Yudhishthir can decide to put Draupadi on "daao" in his game, as as he did with his kingdom and other porperties... then probably it is only justified that we abuse the mother or the sister of the person we want to abuse!

Then again, there are various swear words that refer to male and female genitalia. Does reducing someone/referring to them by their sex organs go to the very core of who they are? I would hope not because surely there is more to us than procreation and sex...however important those may be...so whats the deal with dick/head and cunt and arsehole?

Hmm..points to ponder. Any thoughts?