Do you still go to heaven even if you give your body to science?

Yes, you will, if you give your body to science this is very helpful thing to do. I'm sure God would recognize this as being good works.

In addition, salvation concerns your soul; when you go to Heaven you are given a new body. Your earthly body does not affect your salvation. While good works do not affect your salvation (Ephesians 2:8-9) they are a byproduct of it.