What are the six main structures of the respiratory system?
The respiratory system is rather simple: a breath starts out when a person clenches their diaphragm, creating a vacuum that the air is drawn into. The air enters in the trachea, or windpipe, going through one of the two bronchial tubes, which branch into smaller bronchioles. The bronchioles end in small sacs called alveoli, which have capillaries in them. The carbon dioxide in the blood in the capillaries is then exchanged for the oxygen in the air by diffusion. When that is done, the now oxygenated blood travels all over the body, supplying oxygen where it is needed. Then, the diaphragm relaxes, and the carbon dioxide rushes out of the alveoli, through the bronchioles and the the bronchial tubes, and out of the trachea, and out of the body through the nose or mouth. Then, it is done, and the diaphragm clenches…
