I believe it is class, because species are divided into different classes, but families, for example: there's the cat family, and there's the dog family. classes: the carnivores, herbivores, omnivores OR mammals, egg laying, or hermaphrodites
Answer:
It takes up carbon through physical and biological processes at the ocean surface, carbon dioxide from the atmosphere dessolves in the water
Mitosis occurs in asexual reproduction. It's counterpart is the meiosis, and both are parts of asexual reproduction.
Energy. The other 90% is lost as heat. This is the second law of thermodynamics.