Final answer:
Ventilation and perfusion are two important aspects of gas exchange in the lung. Imbalances in ventilation and perfusion can cause hypoexemia, a decrease in the oxygen levels in the blood.
Step-by-step explanation:
Ventilation refers to the movement of air into and out of the lungs, while perfusion is the flow of blood in the pulmonary capillaries. For effective gas exchange, the volumes involved in ventilation and perfusion should be compatible. However, imbalances in ventilation and perfusion can occur due to factors like regional gravity effects, blocked alveolar ducts, or disease. These imbalances can lead to hypoexemia, which is a decrease in the oxygen levels in the blood.