Respuesta :
The last two statements of the paragraph i.e "Sixty-five percent of the mass of the human body is oxygen. Human beings inhale oxygen and exhale carbon dioxide." indicates that oxygen is important to life.
Answer: Sixty-five percent of the mass of the human body is oxygen
Explanation:
Oxygen is an important element required by the living beings for survival. Our atmosphere contains 20.95% of oxygen. Oxygen is required for cellular respiration and metabolism in living beings, without oxygen no cell in the body of the organisms will survive. It is necessary for the proper functioning of the cell organelles.
In human beings the oxygen is supplied to all the cells of the body by the circulatory system. Therefore, Sixty-five percent of the mass of the human body is oxygen.