What is the primary function of the respiratory system?

The primary function of the respiratory system is to facilitate gas exchange, specifically the intake of oxygen and the removal of carbon dioxide. This process occurs in the alveoli within the lungs, where oxygen from inhaled air diffuses into the bloodstream, and carbon dioxide, a waste product of metabolism, diffuses from the blood into the lungs to be exhaled. This gas exchange is essential for maintaining the body's oxygen levels and ensuring that cells have the energy required for their metabolic functions.

The respiratory system also plays a role in regulating pH levels in the blood, contributing to overall homeostasis. This fundamental role in respiration is vital for sustaining life, as oxygen is crucial for cellular respiration, which powers all bodily functions.