Nitrogen fixation is a process that changes nitrogen within plants and soil into"nitrogen compounds"
Not sure what the choices are but a biotic factor is anything living.
The answer is through the Plasma Membrane
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.