Respiratory System
Across
- 2. the gas moved to the lungs from all living cells
- 5. (5/5/7)these contract and relax during breathing
- 7. main air pipe
Down
- 1. common livestock disease of the lungs
- 3. these have very large surface area for gaseous exchange
- 4. passage this warms and cleans the air coming into the livestock
- 6. maximum breathing rate of a healthy adult cow