The substances that are being used up in cellular respiration are oxygen (O2) and glucose (C6H12O6). They are the main reactants. Cellular respiration happens in the mitochondria, the power house of the cell. Hope this answers the question.
Answer: Earth's seasons are caused by it's tilt on it's axis :)
Explanation:
i would think the answer is B.........
Africa is the most likely where most hominids originated from.
