Across
- 4. produce eggs and sperms
- 8. skeletal system in birds
- 9. shell
- 10. respiratory system of birds
- 12. for grinding food
- 13. line sensation in fish
- 15. movement of mollusks
- 16. lower chambers
Down
- 1. bladder controls fish depth
- 2. skeleton of worms
- 3. large jaws and sharp scales
- 5. bird heart
- 6. sac for wastes in bird
- 7. birds wastes
- 10. waste of fish
- 11. has no scales or jaws
- 14. amphibian heart
- 17. fish heart