Respiratory Physiology

In my Anatomy class we learned about the Respiratory System. There is a certain way that the air flows in and out of our bodies. There are two tracts to our Respiratory System: The Upper Respiratory Tract (URT) and The Lower Respiratory Tract (LRT). The air moves into the mouth (oral cavity) and nose (nasal cavity) then to the pharnyx, the epiglottis (open or closed), then to the larynx (contains vocal cords). This all takes place in the Upper Respiratory Tract (URT). After the air goes to the larynx the air moves to the trachea, to the bronchi, then to the bronchial tree, then to the alveoli where oxygen and carbon dioxide are exchanged, then the air travels out of the lungs in the opposite path. This part of the air flow occurs in the Lower Respiratory Tract (LRT).