Those cells that conduct Aerobic respiration utilize free oxygen as a final electron acceptor in this process, this process is called as aerobic respiration. Oxygen is necessary in Aerobic respiration, and this is the final electron acceptor in aerobic respiration.
While in anaerobic respiration, cell use oxygen-containing ions to create ATP molecules. In anaerobic respiration, there is no need of oxygen, and it occurs in the absence of oxygen.