A BISC 220 student went swimming at the Uytengsu Aquatics Center. Having missed an important lecture on the respiratory system, he thought it would be a good idea to hyperventilate for a minute before diving into the pool and swimming vigorously underwater. Shortly after he began swimming, he lost consciousness and would have drowned if not for the quick action of the lifeguard. Which one of the following best describes what happened? A. Hyperventilation increased the Poz in his blood, which inhibited the brainstem respiratory center.
B. Hyperventilation decreased blood Pco2, which reduced respiratory drive at the same time that exercise increased the demand for O2
C. Skeletal muscle activity caused an increase in blood pH, which suppressed brain function and made him faint.
D. Hyperventilation increased the saturation of hemoglobin with O2, but vigorous exercise caused the bound O2 to be replaced by CO2