Lungs

The lung are the organs responsible for carrying out breathing and gaseous exchange in most air-breathing mammals. They are located either side of the heart and are enclosed by the rib cage which provides protection as well as a minor role in the brathing process. In human lungs, the trachea divides into two bronchi that enter into the base of the lungs. The bronchi continually subdivide into the bronchioles which end in hollow cavities known as the alveoli, where gas exchange takes place.