Answer:
what there's nothing there
Explanation:
The answer is A because the heart pumps blood from the heart through pulmonary artery that is low in oxygen and high in carbon dioxide concentration, to the lungs.
Answer:
they are made to work together and there ae different types
Explanation:
there just made like that
They are thus known as the "supporting cells" of the nervous system. The four main functions of glial cells are: to surround neurons and hold them in place, to supply nutrients and oxygen to neurons, to insulate one neuron from another, and to destroy and remove the carcasses of dead neurons (clean up).