Labels:daily OCR: BRONCHI HE TRACHEA, or windpipe, divides into two tubes known as bronchi (one is called bronchus) which open into the lungs. The walls of the bronchi are made up of rings of tough material called cartilage These keep the tubes open allowing air to pass through. The bronchi themselves divide many times inside the lungs form the bronchial tree. which is a network progressively narrower tubes. These eventually open into the alveoli, or air sacs W here oxygen absorbed into the blood and carbon dioxide is expelled. allow bronch bronchia oxyger
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