What does the Law of Gaseous Diffusion describe?

The Law of Gaseous Diffusion primarily describes the process by which gases move from areas of higher concentration to areas of lower concentration. This is particularly relevant in the context of the respiratory system, where oxygen is transferred from the alveoli in the lungs into the bloodstream.

When you inhale, oxygen enters the lungs and fills the alveoli, where the concentration of oxygen becomes relatively higher compared to the deoxygenated blood in the surrounding capillaries. Due to the principles outlined in the Law of Gaseous Diffusion, oxygen naturally moves from the alveoli (higher concentration) into the blood (lower concentration) until equilibrium is reached. This diffusion is a critical step in respiratory physiology, ensuring that oxygen enters the bloodstream to be delivered to tissues throughout the body.

The other options relate to different physiological processes: oxygen production in the lungs involves metabolic and biochemical processes that do not pertain to diffusion; oxygen transport in the blood is mainly about how it is carried by hemoglobin and dissolved in plasma; and carbon dioxide expulsion involves different mechanisms related to gas exchange but isn't directly described by the Law of Gaseous Diffusion.