It is covered in skin.
This skin excretes a mucous layer which keeps it moist and also acts in protecting the animal from pollutants.
Different types of blood contact different kinds of antigens and antibodies. For example, Type A blood has A antigens and B antibodies, antibodies being the thing that fights B antigens. Type B blood has B antigens and A antibodies. So if someone with type B gets transfused with Type A blood, the person's antibodies will attack the new blood.
I would say different
Like you like different genders
<span>While the open ocean produces little in terms of biomass, it contributes a great amount to the biosphere because of its serving as a habitat for small, primary producers as well as playing a big role in geochemical cycling.</span>
