Nasal Cavity - Air enters the body through the nasal cavity. The walls of the nasal cavity are lined withe little hairs that help stop particles from getting into the body.
Pharynx - The pharynx, which is also called the throat, is directly after the nasal cavity. It is the second place that receives air. Its main function is to transport the air to and from the nose to the trachea.
Alveoli - The alveoli are air sacs found at the end of each bronchiole. They are the site of carbon dioxide and oxygen exchange. Each lung has millions of alveoli. They have very thin walls and are each in contact with a capillary. Oxygen diffuses from these into the cardiovascular system.
Diaphragm - The contraction and relaxation of the diaphragm is what makes breathing possible.
Larynx - Following the pharynx, the larynx is also known as the voice box. It is what allows us to speak. It is triangular shaped and is supported and protected by cartilage.
Glottis - The part of the larynx that holds the vocal chords. It allows us to speak and communicate with sounds. The primary function of the glottis is pronunciation.
Epiglottis - The epiglottis is what closes off the trachea when swallowing and prevents food from entering the trachea. It directs food to the esophagus.
Trachea - The trachea is also known as the windpipe. It divides into left and right bronchi. It is surrounded by cartilage in a "C" shape. This shape allows the trachea to expand and compress so food can pass down the esophagus. It also stops the trachea from collapsing.The trachea transports air to and from the lungs. It is lined with mucous and cilia.
Bronchi - The bronchi transport air from trachea into the lungs. They are two large tubes that take air from the trachea and deposit it in the right and left lungs.
Bronchioles - Each primary bronchus divides into smaller beaches called bronchioles. Air passes through these in order to get to the alveoli.
Lungs - These are the most important organs of respiration. They store the air.
Alveolar Ducts - Distal to the bronchioles, the alveolar sacs and alveoli come from the ducts.