Final answer:
The primary function of the respiratory system is to exchange gases and support cellular respiration by delivering oxygen to the body's tissues and removing carbon dioxide as waste. The major organs involved in this process include the nasal cavity, trachea, and lungs.
Step-by-step explanation:
The primary function of the respiratory system is to exchange gases (oxygen and carbon dioxide) to support cellular respiration. It delivers oxygen to the cells of the body's tissues and removes carbon dioxide, a waste product. The major organs of the respiratory system, such as the nasal cavity, trachea, and lungs, are involved in this gas exchange process.