Physiology A 49-year-old man has a pulmonary embolism that completely blocks blood flow to his left lung. As a result, which of the following will occur? A Ventilation/perfusion (V/Q) ratio in the left lung will be zero B Systemic aerial PO2 will be elevated C V/Q ratio in the left lung will be lower than in the right lung D Alveolar PO2 in the left lung will be approximately equal to the PO2 in inspired air 💡 Explanation A 49-year-old man has a pulmonary embolism that completely blocks blood flow to his left lung. As a result, which of the following will occur? ✓ Correct Answer: D. Alveolar PO2 in the left lung will be approximately equal to the PO2 in inspired air