Video Transcript
What organ system is shown in the diagram?
To determine what organ system we are looking at, let’s first label the different
parts we can see in the diagram.
In the head, we have the nose, mouth, and pharynx. The pharynx is the passage at the back of the throat where the nose and mouth
connect. In the neck region, we have the larynx, another passage which is often known as the
voice box because it contains the vocal cords. The larynx also forms the upper part of the trachea, the cartilaginous structure
which runs from the neck down into the chest.
In the chest, the trachea splits into two branches, each of which is known as a
bronchus. Each bronchus then branches off into smaller vessels called bronchioles inside the
lungs. At the end of the bronchioles are air sacs called alveoli. These are the site at which oxygen and carbon dioxide are exchanged with the
blood.
At the bottom of the chest, we have a curved muscle called the diaphragm, which can
contract and relax to increase and decrease the volume of the chest. Surrounding the lungs are the ribs, and between the ribs are the intercostal
muscles.
All the structures we have labeled work together to carry air into and out of the
lungs through the process of breathing, which is also termed ventilation. Ventilation is vital because it’s what ultimately provides every cell of the body
with the oxygen it requires for cellular respiration.
This organ system is therefore known as the respiratory system.
