The Respiratory System
The respiratory system is made of seven main components; the nose, pharynx, larynx, trachea, bronchus, lung, and diaphragm. The nose is an airway for air to come through into the pharynx. The pharynx is the passage from the mouth to the larynx and esophagus. Then the air travels through the larynx AKA the voice box. After that, air goes through the trachea, the connection tube between the larynx and the bronchia. A bronchus is one of the tubes that connect the trachea to the lungs. From there, air travels through a series of progressively smaller tubes that eventually reach the lung wall where blood drops off carbon dioxide and picks up oxygen. Then carbon dioxide takes the same trip that the oxygen did but in reverse. The diaphragm assists in the exchange of gasses by expanding when breathing in and tightening when you breathe out. This process happens tens of thousands of times throughout the day. The respiratory system relates to the cardiovascular system because the lungs oxygenate the blood that comes through there. The respiratory system relates to the nervous system because the brain tells the diaphragm to move at certain times. It also relates to the skeletal system because the ribcage protects the lungs. The muscular system relates to the respiratory system because it is the muscle cells that get most of the oxygenated blood to deliver oxygen and carbon dioxide.
The picture to the left depicts a diagram of the human respiratory system.
These are human lungs.