Answer:
Well, Earth is the same way! Earth is made up of several different layers, each of which has unique properties. Both parts of the core are made up of mostly iron and some nickel. The difference is that in the inner core, those minerals are solid and in the outer core, they're liquid.
It is used by every living cell.
Cellular respiration is a process of combining oxygen with foodstuff molecules, diverting the chemical energy in these substances into life-sustaining activities and discarding, as waste products, carbon dioxide and water.
Matter can be recycled, but energy cannot. Also, only 10% of the energy is passed through each trophic level.