The respiratory tract as a whole is an organ system that's composed of the lungs and airways. It plays a role in gas exchange. The respiratory system works closely with our circulatory system to deliver important gases such as oxygen to our cells and tissues. It also helps to remove gases such as carbon dioxide from our tissues as we breathe in and out.
The respiratory system can be broken down into two sections, the upper respiratory tract and the lower respiratory tract. Let’s focus here on the different structures associated specifically with the upper respiratory tract, labeled in green.
The nasal cavity is an airway in your nose where air enters and is then moistened, filtered and warmed. The oral cavity is a location associated with our upper respiratory tract where air can enter. The oral cavity is like a backup airway if breathing is labored or heavy.
The pharynx, also known as the throat, is where the nasal cavity and the oral cavity converge. The pharynx connects the nasal and oral cavity to the larynx.
Larynx is also known as the voice box and is an airway where sound is produced. As air moves through the larynx, sound can be produced. This is how you are able to make sounds to speak.
The next structure that we're going to discuss is the trachea, also known as the windpipe. The trachea connects the larynx with the bronchi and the lungs, which are a part of the lower respiratory tract. The trachea is the connective tube between the upper and lower respiratory tract. The trachea is a flexible tube that's reinforced with cartilage bands.
The esophagus is not a part of the upper respiratory system but sits close to your trachea. The esophagus is the tube that carries food down to your stomach. The epiglottis is the flap of skin that closes off your trachea when you're swallowing food. This is important because as you're eating and swallowing food, it closes off your trachea to make sure that food will then go down your esophagus into your stomach and won't accidentally go down your trachea and then into your lungs.
Source: THIS WORK IS ADAPTED FROM SOPHIA AUTHOR AMANDA SODERLIND