Final answer:
Diffusion issues typically impact oxygen levels first, because oxygen's uptake is crucial for cellular respiration, despite carbon dioxide having a faster diffusion rate and a higher affinity for hemoglobin.
Step-by-step explanation:
Problems with diffusion often affect the levels of oxygen first, despite the fact that carbon dioxide diffuses faster than oxygen. This is because oxygen is primarily transported in the body by dissolving in blood and binding to hemoglobin, and it is essential for cellular respiration. Carbon dioxide indeed has more affinity for hemoglobin than oxygen; however, it is more soluble in plasma, facilitating its diffusion into the alveoli.
During gas exchange, oxygen diffuses out of the capillaries and into cells, while carbon dioxide diffuses out of cells and into the capillaries. Specialized respiratory tissues and circulatory systems have evolved to efficiently transport oxygen and remove carbon dioxide, maintaining the necessary gradient for diffusion. Consequently, issues with this system typically manifest as inadequate oxygen levels before they affect carbon dioxide levels.