I am doing a crossword puzzle for the Circulatory and respiratory systems review. If you can say them all I will give you 22 points. If you need to know how many letters ask in comments.
3.Pumps blood to heart
6.What returns fluid that leaks from capillaries back to the circulatory system
7. branching system of tubes which sends air to the alveoli
9. contains blood with little oxygen and a lot of carbon dioxide
15. a dangerous tumor in the respiratory system.
16. muscle that relaxes when you exhale.
19.moves substances through the body.
Down:
5.Separates the atria from the ventricle ; keeps blood flowing one way
8. thin walled blood vessel that allows for gas exchange
11. hair like structures that line the trachea and nose
12. receives blood from the lungs
17. movement of air in and out of lungs
18 location of gas exchange in the lungs
20. oxygen transport blood component