Answer:Variation in traits can be caused by variation in protein molecules within individuals' cells. Protein molecules' structures affect their function and the way they connect to other molecules.
Explanation: ^^^ hope it helps :)
I think you're confused. There are only two sexes, male and female. Sex is what you were biologically born as from birth, while gender is what you choose to identify as. Gender is a choice, sex isn't. They couldn't discover any other genders because at the time they probably didn't even know what gender was like three thousand years ago, therefore they couldn't look like a different gender.
Answer: Water molecules bond well.
Explanation: Water hold up quite well mostly because the water molecules are attached to each other.
