The trachea is the organ in the respiratory system that connects the larynx (voice box) to the bronchi of the lungs. The trachea ranges from about ten to twelve centimeters in length and sixteen to eighteen millimeters in width. In the throat, the trachea begins around the bottom of the larynx, and then moves down to the lungs, breaking off into two bronchi.  The larynx has between sixteen and twenty rings that support and uphold the throat. These rings are able to bend and adjust to the task being done. The trachea is made of cartilage and is lined with cells that create mucus to help protect the trachea from particles getting lodged and stuck. The trachea allows us to swallow food thus aiding in digestion. Because the trachea is one of the main air passageways, if blocked it can be fatal. When blocked, doctors must place a tube down the throat allowing air to pass through (intubation). The trachea has been known to be an organ that can be infected with many sicknesses such as tracheitis, tracheobronchitis, tracheomalacia, and trachea cancer  .
The trachea is a windpipe that is located at the front of the throat. It measures approximately 4 inches long and .6 to .7 inches wide. The trachea begins just below the the larynx (voice box), and goes all the way down into the lungs where it then branches out to the side bronchi. The trachea is made up of 16-20 C-shaped rings that go down the throat line.  The rings are made of tough cartilage. The rings are connected by elastic connective tissue which allow them to move. This is called the trachealis muscle. The muscle is then able to contract and move according to the action taking place. Connective tissue and muscle make up the back of the rings, and on the inside of the rings there is a moist, smooth tissue called mucosa lines. The rings are also not fully connected, they are shaped like a "C", and that allows food to pass through the esophagus because the trachea is next to the posterior wall, thus allowing food through.  The trachea appears as an incredibly intricate design although the rings are made of tough cartilage, they were created to enlarge and contract. With every breath that a person takes, the trachea enlarges when the person inhales, and contracts when they exhale. The good Lord thinks of everything.  The inside of the trachea is lined with cartilage, just before it breaks off into the bronchi. The bronchi then break off into many smaller branches in the lungs.  These rings also protect the windpipe so that air may travel through the passageway. Without these rings, the neck could potentially become damaged, causing the person to stop breathing and suffocate. 
The trachea is the main passageway for air to and from the lungs. Without the trachea, there would be no space for the air to pass through and people would die from suffocation. Inside the trachea, the rings are important because they give structure to the throat. Without the trachea rings the throat would collapse. The flexibility of the trachea also plays a major role because when people eat and breathe, the trachea bends accordingly. The trachealis muscle that connects the rings help with the flexibility.  The cells that line the trachea are also of extreme importance because they trap the particles and create mucus. The mucus is created by the cells inside the trachea, goblet cells and ciliated epithelial cells. The mucus that is created then helps in making the air more moist. The mucus then traps the unneeded particles, moves them through the larynx and pharynx, and then deposits them into the stomach.  The trachea is also important because it is vital for the digestive system. The trachea is a passageway for food and allows swallowing. Nothing can block the passageway or it will result in coughing and choking. 
The main function of the trachea is a passageway for air to move into and out of the lungs. Through transporting the air, the exchange of oxygen rich air and carbon dioxide rich air takes place. The inside of the trachea is lined with mucus creating cells which moisten the air by creating mucus. The cells also trap other dust particles and they then pass through the larynx and create phlegm. The passageway splits into two bronchi that go into the lungs, helping people breathe easier. If food clogs the passageway, the respiratory system forces the person to cough, causing the food to be removed from the trachea, and allowing the person to breathe. Because it is the main passageway, if it is blocked by damage, intubation must take place. This is where doctors place a tube in the nose or the mouth and it passes through the trachea so that they can breathe easier. 
There are many medical conditions that have to do with the trachea such as tracheitis, tracheobronchitis, tracheomalacia, trachea cancer, a collapsed trachea, and many other things. When dealing with tracheitis, the persons trachea is inflamed. The bacteria or infection can cause swelling, difficulty in breathing, coughing, high fever, and a higher voice. This infection mainly affects children because their throats swell easily. This infection can be deadly if not treated quickly because the air passageway can be swollen and they then need a tube to breath.  Next, tracheobronchitis appears to be a combination of tracheitis and bronchitis. This seems more serious than bronchitis though because it can be associated with chemical and/or physical irritants, viruses, and bacterial infections. Symptoms of tracheobronchitis are coughing up phlegm, coughing, fever, and sputum (saliva mixed with mucus or pus, expectorated from the lungs and respiratory passages). There are not many treatments except antibiotics and self healing.  Tracheomalacia is when the C-shaped rings in your trachea are not strong enough to support the trachea and keep it open. This happens to a small percentage of children but they must have surgery to strengthen the rings and keep the air passageway open. If not, the child has extreme difficulty breathing. Many children who have it either outgrow it by the time they are two, or it is not bad enough to require surgery.  Trachea cancer is also another unfortunate thing that can happen. Finding cancer in the trachea is extremely rare, yet difficult to cure when it happens. Some instances have been traced back to smoking, and other causes are unknown. This is extremely hard to cure because they obviously cannot remove the trachea, so they try to remove some of the cancer but if they cannot remove all of it then they use radiotherapy to kill the rest. 
- Wile, Jay L., and Shannon, Marilyn M. The Human Body: Fearfully and Wonderfully Made!. Cincinnati: Apologia Educational Ministries, Inc., 2001. 417. Print.
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