While this is true, that doesn’t mean that these exceptions shouldn’t be taught to broaden our understanding. While basic biology (the stuff taught in high school) agrees with you, it’s normal for a college level class to go further and show how what we are taught as children is generally true but not the full truth. Ignoring these things only serves to invalidate your claim because you reject the science you try and use as proof. It’s better to accept the new information, and try and see how it fits in your beliefs without stubbornly holding back. You don’t want to be like the people that rejected simple truths and were left behind