The Respiratory System
The Path of Air
The Path of Air Air enters through the nose or mouth Air passes through a muscular tube called the pharynx Air then passes through the larynx, or the voice box Air enters the trachea, a long tube in the chest cavity
Path of Air The trachea divides into smaller tubes, the bronchi, which leads to the lungs The bronchi divide into smaller tubes called bronchioles The bronchioles end in air sacs called alveoli Surrounded by capillaries
Lungs One of the largest organs in the body Diaphragm aids in respiration Breathing is caused by pressure changes What influences the breathing rate?
Oxygen Transport Oxygen diffuses from alveoli to the capillaries Oxygen travels to the heart and is pumped to the rest of the body
Carbon Dioxide Transport Carbon dioxide diffuses from the cells to the blood. Bicarbonate The heart pumps the blood to the lungs. In the lungs, carbon dioxide is released
Respiratory diseases Asthma Emphysema Lung cancer