Beginning of Essay
The main job of is to provide oxygen to the blood, and release the carbon dioxide left over from the spent blood, works with the cardiovascular system to make this happen. Blood enters the lungs through the pulmonary circulation and is dark colored, low in oxyge ....

Middle of Essay
.... is a hollow chamber in which the voice is produced, at the upper part of the windpipe; it is also called the voice box. It leads from the lower portion of the pharynx to the trachea and is next to esophagus, behind the skin and connective tissue of the throat. The larynx is supported by ligaments from the hyoid bone, at the base of the tongue. Going into the trachea The trachea, is a section of respiratory tract in the neck, extending between the larynx and the bronchi and lying in front of the esophagus. The trachea, also called windpipe, is made up of numerous cartilaginous half-rings, the open ends are near the esophagus. These rings, located one ....