D. population and nutrients
Answer:respiratory system
Explanation:The primary function of the respiratory system is to deliver oxygen to the cells of the body's tissues and remove carbon dioxide, a cell waste product. The main structures of the human respiratory system are the nasal cavity, the trachea, and lungs
This occurs when a molecule of adenosine diphosphate (ADP) uses the energy released during cellular respiration to bond with a thirdphosphate group, becoming amolecule of ATP. So the energy from cellular respiration is stored in the bond between the 2nd and 3rdphosphate group