The respiratory system is responsible for gas exchange between the body and the environment, providing oxygen to cells and removing carbon dioxide. Air enters through the nose or mouth, passes through the pharynx and larynx, and then reaches the trachea. The trachea splits into two bronchi, which branch into increasingly smaller bronchioles, eventually reaching the pulmonary alveoli.

In these tiny air sacs, gas exchange occurs as oxygen moves from the alveoli into the bloodstream, and carbon dioxide is released from the capillaries into the alveoli to be expelled during exhalation. The diaphragm and intercostal muscles facilitate the processes of inhalation and exhalation by expanding and contracting the lungs.