Across
- 4. the respiratory system that birds have.
- 7. everything hole.
- 9. store oxygen for birds to make respiration more efficient.
- 10. bone that provides birds with more stability for flight.
- 11. the muscle thatprovides the downstroke of the wings.
- 13. muscular organ that grinds up food with grit.
- 14. name of the third eyelid membrane in birds.
Down
- 1. stimulates birds to breed includes temperature and sunlight hours.
- 2. the true stomach of birds.
- 3. makes the birds more lightweight for flight.
- 5. the vertebrae of the neck that only birds can have more than 7 vertebrae.
- 6. the bone that angles the tail, allowing birds to turn in flight.
- 7. storage organ.
- 8. provides insulation, aids in flight and camouflage.
- 12. the muscle that provides the upstroke of the wings.