Cake and sex are both things you can have an appetite for. But it's only an appetite for the food, or the sex. Your preference may be only for cake, or a specific gender though. Generally, you can't consciously decide to enjoy the taste of something. Your body decides that for you. Same for sexual preference.

We have healthy food, and unhealthy food. In general, someone who is addicted to food is addicted to unhealthy food...I haven't heard of a case where someone was addicted to fruits and vegtables.
Sex is along the same lines. It's something that the human race needs, in order to continue, and at the same time it's pleasurable. It's only human nature to exploit it into something also unhealthy.

We're designed that when a male and female have sex, there is a chance of creating a baby. But what about oral sex? Is oral sex between a man and woman wrong, because there is no chance of a baby being made? What about anal sex between a man and a woman?

The bible talks about sex in a physical, AND spiritual way. Sex between a husband and wife is pleasurable and brings them closer together on a spiritual level. Any sexual activity, if it's between two married people is not only "allowed" (provided it's a positive use) by God, it's also "blessed". The bible clearly says that men and women were built for one another in not only physical ways, but emotional, and spiritual ones as well. Two men would never share the same "spiritual" closeness that a husband and wife could have during sex.

And, yes there is a physical difference - not on the outside, but on the inside, in the genetics - beachguy in thongs has given you evidence for that.

He has given me evidence supporting a theory. The evidence is there alright, but keep in mind we hardly know anything about the brain, let alone how the mind might manipulate it.

No, it doesn't. They are born one way or another, because it's part of their genetics. When they develop a sex drive it will be aimed at one sex or another, or both.

That's an assumption based on whether or not the above is correct. You're saying that when a baby is born, it's "programmed" to either be gay, straight, or bisexual when it hits puperty (roughly the age when girls and boys become attracted to another)...the thing is that there's an 8-12 year window of opportunity for that childs mind to develope either one way or the other, and we hardly have any idea of how experiences and psychological trauma/manipulation might affect this child...

Think of it like height. We obviously aren't born at the height we will eventually grow to be, but we will eventually reach that height.

But there's no limit to the heights we could grow (to an extent). There are so many things like nutrition, excersise, and posture that change these things. With sexual orientation, it would be like saying that we're either born to be 5ft6, 6ft5, or both

Sex left in the hands of humanity? What do you mean by that? They've recently discovered evidence of the first gay kiss - as an Egyptian wall mural. It's not something that's happened recently because we've become bored with hetero sex!

The bible has a story about a place called Sodom, where the people there had become so sexually corrupted that the whole town turned to homosexuality. Homosexuality is a very old thing indeed. It's not something that's ever had to evolve, because it's always been there. It takes time to grow, but it's ever present. I'm not arguing that homosexuality is a new thing, but I AM arguing that it's only NOW started to become a globally accepted thing. It's because as humanity is starting to gather itself together (which on the outset would be a good thing) it also uses this "unity" to corrupt itself on a much larger scale. Instead of multiple divided groups making multiple small mistakes, we're starting to have one large group making one large mistake.

But it isn't a divine creation. It's just a simple fact of life. It's the way we procreate. There is no perfect purpose, there is no right way to get your happies! It's an animal instinct, not something we do because God thinks we should. I'm not Christian, and I enjoy a healthy sex life, nothing to do with a higher power.

Sex is a simple fact of life because it is a divine creation. It is something that is only pleasurable because God has given us that pleasure to share with our spouse. Unlike animals, we actually fall inlove with our mates, therefor sex could hardly be JUST a physical thing. Sex is physically pleasurable, but it's also spiritually/mentally pleasureable, and it's ONLY fullfilling its full use when it's in a married situation.