Final answer:
Cellular respiration is a biochemical process in cells that generates energy, requiring oxygen and producing carbon dioxide, while external respiration is the exchange of gases in the alveoli of the lungs, including the inhalation of oxygen and the exhalation of carbon dioxide.
Step-by-step explanation:
The difference between cellular respiration and external respiration is distinct. Cellular respiration is the metabolic process by which cells generate energy (in the form of ATP) by "burning" glucose with the use of oxygen and releasing carbon dioxide as a byproduct. It involves not just the respiratory system, but also requires the digestive and cardiovascular systems to provide the necessary glucose and oxygen, and to remove the carbon dioxide produced.
External respiration, on the other hand, refers to the gas exchange process that occurs in the alveoli of the lungs, where oxygen is taken into the blood and carbon dioxide is expelled into the atmosphere. The breathing process is a part of external respiration, as it involves the physical movement of air into and out of the lungs, while cellular respiration refers to the biochemical process inside cells.