Across
- 3. tooth-like skin of a cartilaginous fish
- 5. takes oxygen from air
- 6. gives bony fish buoyancy
- 7. control body temperature through chemicals reactions of cells
- 8. ancestors of mammals
- 14. row of tiny organs that detects movements
- 17. animal with backbone
- 18. fluffy and helps birds stay warm
- 20. remove oxygen from water
- 21. change from larval to adult form
- 24. secrete a nutritious fluid
- 26. do not control body temperature
Down
- 1. makes sreamlined flying surface
- 2. muscle that brings air into lungs
- 4. time where embryo develops
- 9. protect a fishes body and reduces friction while swimming
- 10. protects and keeps embryo from drying out
- 11. mammals with pouches
- 12. process of spreading oil on feathers
- 13. embryos that stay inside the mothers body
- 15. upward force to keep birds in the air
- 16. make up the backbone
- 19. help fish move, steer, stop, and balance
- 22. process of sitting on eggs to keep them warm
- 23. aquatic larva of amphibian embryo
- 25. mammals that lay eggs