The respiratory system supplies the blood with oxygen to be delivered to all parts of the body. The system does this through breathing. The air we breathe in (inhalation) is rich in oxygen, which is used by body tissues to maintain life functions. We exhale the carbon dioxide that these tissues produce as a waste product. The parts of the respiratory system are the oral and nasal cavities, the trachea, the bronchi, and the lungs.
More than 300 million alveoli lie at the final stage of this process. Zooming in will enable you to see the gas exchange going on at the level of these tiny structures.
You also have access to numerical data on the composition of inhaled and exhaled air, and of oxygenated and deoxygenated blood.
Click on to activate the cycle.
Click on to zoom in.
- To understand the exchange of oxygen and carbon dioxide occurring at the level of the alveoli.
- To visualize gas exchange between blood and body tissues as a result of the functioning of the respiratory and circulatory systems.