Final answer:
Carbon dioxide (CO2) is the gas produced by cellular respiration and dissolved into the blood for removal from the body. It diffuses out of the cells into the blood and is transported to the lungs, where it is exhaled.
Step-by-step explanation:
The gas produced by cellular respiration and dissolved into the blood to be removed from the body is carbon dioxide (CO2). During this metabolic process, glucose is "burned" in the presence of oxygen to generate energy in the form of ATP. For each molecule of glucose, a net total of 36 or 38 molecules of ATP can be produced, with carbon dioxide being one of the major end products released. This carbon dioxide diffuses out of cells, due to it having a lower partial pressure in the blood compared to the tissues, and then it crosses the interstitial fluid before entering the bloodstream.
In the blood, carbon dioxide is carried to the lungs in three forms: bound to hemoglobin, dissolved in plasma, or in a converted form such as bicarbonate. About 7 to 10 percent of carbon dioxide is dissolved directly in the plasma. Once it reaches the pulmonary capillaries, the dissolved carbon dioxide diffuses across the respiratory membrane into the alveoli and is then exhaled during pulmonary ventilation. This elimination of carbon dioxide from the body through exhalation is a critical component of respiratory gas exchange.