Respiratory system

3. - a that supports the lungs in pulling in air and pushing it out.
6. - tiny hairs that move in a wave-like motion to filter dust and other irritants out of your airways.
8. - a tissue flap at the entrance to the trachea that closes when you swallow to keep food and liquids out of your airway.
11. tubes/bronchi - tubes at the base of the windpipe that connect into each lung.
12. - hollow areas between the bones in our head that help regulate the temperature and humidity of inhaled air.

1. - small branches of the bronchial tubes that lead to the alveoli.
2. - blood vessels in the alveoli walls that move oxygen and carbon dioxide.
4. sacs (alveoli) - tiny air sacs in the lungs where the exchange of oxygen and carbon dioxide takes place.
5. (voice box): a hollow organ that allows us to talk and make sounds when air moves in and out.
7. (trachea) - a passage that connects our throat to our lungs.
9. - Two organs that deliver oxygen from the air to our red blood cells. They also help the body get rid of CO2 gas (a waste gas) when we breathe out.
10. (pharynx) - a tube that transports air from the mouth and nose to the trachea (windpipe).