Systems Crossword Puzzle

3. We have two of these so we can still breathe if one is stopped up with a cold.
5. The respiratory system includes these two organs.
6. As we exhale, small amounts of water and ___ exit.
10. These exchange gas between inhaled air and the bloodstream.
11. This stops food from obstructing the trachea.
12. Excretes body heat.
13. What gas do plants give off that we need?
14. The excretory system eliminates ___ and regulates our body temperature.
16. The hollow space behind the nose is the nasal ___.
17. The larynx houses the ___.
18. The urinary tract, lungs, skin, and intestines make up this system.

1. ___ hairs and mucus filter dust in airway passages.
2. These organs filter the blood.
4. These smaller tubes branch out from the bronchi.
7. The number of breaths an average person takes will ___ with physical activity.
8. Urine collects and is stored here.
9. What gas do we give off that plants need?
11. Release carbon dioxide.
15. Also known as windpipe.
18. The trachea is in front of what other tube?