Respiratory System

3. (O₂)- A gas from the air that the body needs for respiration.
4. Tiny air sacs in the lungs where oxygen and carbon dioxide are exchanged between the air and blood.Diaphragm- A muscle under the lungs that helps with breathing by moving up and down.
11. The process of breathing out air with carbon dioxide.Gas Exchange- The movement of oxygen into the blood and carbon dioxide out of the blood at the alveoli.
12. Smaller branches of the bronchi that lead to the alveoli.

1. Organs where gas exchange happens – oxygen enters the blood and carbon dioxide is removed.
2. Two tubes that branch from the trachea into each lung.
5. The process of breathing in oxygen-rich air.
6. A chemical process where glucose and oxygen are used to release energy in cells.
7. (Windpipe)- A tube that carries air from the mouth to the lungs.
8. A sticky fluid that traps dust and germs in the airways.
9. Tiny hairs that move mucus and trapped particles out of the lungs.
10. Dioxide (CO₂)- A waste gas produced by cells during respiration; it is breathed out.