Human Body

2. The place were chemicals are injected into the small intestine
7. small spheres in the lungs which are referred to as "air sacks"
9. the largest blood vessel
10. the vein which carries oxygen poor blood to the lungs
11. things in the digestive system that prevent food from moving forward. These things contract when food cannot go forward.
13. increases surface area in the rest of the small intestine

1. the windpipe
3. diffusion of water
4. the small "roads" in the lungs were oxygen and CO2 travel
5. the vein which carries oxygen poor blood to the heart
6. a flap in the throat that makes food do into the stomach and air into the lungs
8. the voice box between the throat and windpipe
10. the throat
12. something that breaks down protein in the stomach