Which system includes the nose, mouth, throat, lungs, and muscles for gas exchange?

The correct answer is the respiratory system because it is specifically responsible for the process of gas exchange. This system includes various anatomical structures such as the nose, mouth, throat (pharynx), trachea, bronchi, and lungs.

These components work together to facilitate the inhalation of oxygen-rich air and the exhalation of carbon dioxide, a waste product of metabolism. The muscles involved, including the diaphragm and intercostal muscles, assist in expanding and contracting the lungs during breathing, which is essential for effective gas exchange at the alveolar level.

Understanding the function of the respiratory system is critical since it directly impacts the oxygenation of blood and the removal of carbon dioxide, both vital for cellular metabolism and overall homeostasis. The other systems listed serve different functions: the circulatory system transports blood and nutrients; the endocrine system regulates hormones; and the nervous system controls body functions and responses.