The respiratory system allows the exchange of oxygen and carbon dioxide to and from the blood. It provides a passageway for air to enter and leave the body through its conducting portion as well as the site for gas exchange through its respiratory portion (Mescher, 2021). The respiratory system contains the following structures among many others:
1. Lungs – The lungs contain many alveoli, which are the cellular sites of the exchange of oxygen and carbon dioxide.
2. Epiglottis – The epiglottis is a flap of tissue that serves to keep food and water from entering the trachea during swallowing.
3. Trachea – This is where the air passes through to go to the bronchi.
4. Larynx – This connects the nasal cavity and the trachea. This is also where we can find our vocal cords, which produce vocalization.

Mescher, A. (2021). Junqueira’s basic histology: Text & atlas. McGraw-Hill Education.