The respiratory system is the complex biological mechanism responsible for gas exchange, which is essential for aerobic metabolism. Its primary function involves taking in oxygen, necessary for cellular respiration, and expelling carbon dioxide, a metabolic waste product. This system comprises a series of airways, including the nose, pharynx, trachea, and bronchi, which transport air to the lungs. Within the lungs, millions of tiny air sacs, or alveoli, are enveloped by capillaries, forming the site of gas exchange. Specialized physical and chemical processes, such as ventilation and diffusion, drive the movement of gases across the respiratory membrane to maintain the necessary partial pressures for life.