TORONTO -. Mike Babcock's first exhibition schedule as coach of the Maple Leafs will take him to some interesting arenas.
There are two types of 'respiration': pulmonary (visible breathing) and cellular (which is not visible). In pulmonary respiration the unwanted gas expelled is mainly carbon dioxide. This is then replaced during the inhalation breathing phase by the oxygen content in the air.
Respiration in the sense of gas exchange is the process by which an organism absorbs the gases necessary for its cellular metabolism from the environment and expels the gases that are the products of this metabolism.