2. Use the word bank to match the term to the definition and to fill in the blanks below.
lungs diaphragm nasal passages
trachea bronchi alveoli
1. These little sacs are where carbon dioxide leaves the blood and
oxygen enter it.
2. This large muscle helps you fill and empty your lungs.
3. You inhale air through these about 20 times a minute.
4. Two large, and very important, organs inside your chest cavity.
5. This tube that carries air to lungs.
6. The tube inside the lungs that leads to the alveoli.
Respiration begins in the , where air comes into the body.
Air travels through the to the . The
pushes up and down to fill and empty the lungs. Inside the lungs,
air in the travels to the small sacs called . Inside
those small sacs is where the important gas exchange occurs