If your immune system attacks your own body parts, then it's called 'autoimmune disease'.
Autoimmune disease can happen at many times due to many problems the body can have. If one thing goes wrong with your body, it can go to another.
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.
An ecosystem is the biotic and abiotic factors which are responsible for the survival of an animal
<span>To get energy. Sugars are particularly important fuel molecules. They are oxidized in the food we eat and must be broken down into smaller molecules before our cells can use them
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