chenge4444

Hi all, I got this question on my test: "Marco tries to hide at the bottom of a swimming pool by breathing in and out through a long garden hose (2 feet in length), which greatly increases his dead space. What happens to the bicarbonate level in his arterial blood and why?" I think breathing under water would increase his arterial bicarbonate levels. Is this correct? 90% of CO2 is the blood is transported as bicarbonate ions. My professor thinks this is incorrect because she said that blood CO2 is only 40nm and blood HCO3 is 24 mM, so even doubling the amount of arterial CO2 would not make any differences. But I think 40nm is the concentration of H+, the concentration of arterial CO2 is actually 21 mM. My professor and I exchanged about 4 or 5 emails each. I don't want to waste her time unless I'm certain that my understanding is correct.