Which physiological function is primarily performed by the lungs?

The primary physiological function performed by the lungs is gas exchange. This process involves the uptake of oxygen from the atmosphere into the blood and the removal of carbon dioxide from the blood into the atmosphere. Within the alveoli, which are tiny air sacs in the lungs, oxygen and carbon dioxide are exchanged across the respiratory membrane due to differences in partial pressures. This process is crucial for maintaining proper oxygen levels in the bloodstream, supporting cellular metabolism, and removing waste products from the body.

While the lungs play a role in toxin elimination by expelling some gaseous waste products, their primary role is distinctly focused on gas exchange rather than general detoxification or the regulation of fluids. Nutrient absorption is instead performed by the digestive system, while fluid regulation involves mechanisms managed by the kidneys and other body systems. Understanding this fundamental function of the lungs helps to highlight their essential contribution to overall respiratory physiology and homeostasis.