| A | B |
|---|
| Respiratory System | A group of organs and tissues that exchange oxygen and carbon dioxide between your body and the enviroment. |
| Lungs | The main and major organs of your respiratory system. |
| Bronchi | The tubes that branch from the trachea. |
| Alveoli | Place in the lungs where the gas exchange occurs. Called also air sacs. |
| Trachea | Called also windpipe, warm clean air travels down the trachea, in your chest the trachea divides into two large tubes called bronchi. Each one leads to a lung. |
| Pulmonary Arteries | Structures that carry oxygen-poor blood from the heart to the lungs. |
| Pulmonary Veins | Structures that carry oxygen-rich blood from the lung to the heart. |
| Bronchioles | Smaller tubes into which the bronchi branches off. These tubes are as thin as hair. There are about 60.000 bronchioles in the lung. They branch off into almost 700 million alveoli. |
| Diaphragm | A layer of muscle beloww your lungs that allows air to fill the lungs. |
