Final answer:
Carbon dioxide produced by rats in a sealed chamber accumulates unless chemically removed; in living organisms, it is converted into bicarbonate for transport in blood and expelled via the lungs.
Step-by-step explanation:
The carbon dioxide produced by rats in a sealed chamber would accumulate in the chamber unless it was chemically absorbed or converted into another substance. In a biological context, such as within the blood of an animal, the carbon dioxide is often converted into bicarbonate through the action of the enzyme carbonic anhydrase. This process is crucial for the transport of carbon dioxide in the blood away from the tissues, as it diffuses down its concentration gradient from areas of higher pressure in the blood (45 mm Hg) to areas of lower pressure such as the alveoli (40 mm Hg).
The majority (85%) of carbon dioxide is carried as part of the bicarbonate buffer system. In this system, carbon dioxide enters the red blood cells and gets converted to carbonic acid, which then dissociates into bicarbonate and hydrogen ions. The bicarbonate ions get transported in the blood until they reach the lungs, where the reaction reverses and carbon dioxide is regenerated from bicarbonate to be exhaled.