Answer the following question given this paragraph: Keeping the rate of metabolism high takes a constant and plentiful supply of oxygen. That's because cellular respiration, which produces energy, requires oxygen. The lungs and heart of mammals are adapted to meet their oxygen needs. Q: A constant and plentiful supply of oxygen is required in order to maintain a high rate of what? Choices: - digestion - cell division - magnesium - metabolism A:
The answer to this question is:
metabolism