Respiratory

3. The outermost layer of plant tissue that contains stomata.
6. Small openings on the surface of plant leaves that allow for gas exchange.
7. Openings on the surface of the body of terrestrial arthropods that allow for gas exchange.
8. A dome-shaped muscle that aids in the process of breathing.
9. The movement of molecules from an area of higher concentration to an area of lower concentration.
11. Respiratory organs in terrestrial vertebrates that facilitate gas exchange.
12. Respiratory organs in fish that extract oxygen from water and release carbon dioxide.

1. A protein in red blood cells that binds to oxygen and transports it in the blood.
2. Tiny air tubes in insects that transport gases to different parts of the body.
4. The process by which plants convert carbon dioxide and sunlight into oxygen and glucose.
5. Tiny air sacs in mammalian lungs where gas exchange occurs.
10. A gas necessary for cellular respiration and energy production.