Across
- 4. bone hardening
- 7. chordate that has a vertebral column
- 9. egg laying mammals; echidnas
- 10. bone tissue that is strutted and allows strength without adding weight
- 13. series of changes that animal goes through to reach maturity
- 15. have hair and mammary glands
- 16. to lay eggs
- 17. valve valves found where blood leaves the heart
- 20. joints immovable joints like sutures
- 22. hooves mammals
- 25. glands structure that provides milk for the young in mammals
Down
- 1. to produce eggs
- 2. marrow stores fat but can convert in emergencies to be able to produce blood cells
- 3. structure of mammals that nourishes the embryo
- 5. venom that attacks the nervous system
- 6. muscle type of tissue that produces contractions that move bone--voluntary
- 8. marrow where blood cells are produced inside bone
- 11. cava large vessel that returns blood to the RA
- 12. tissue tissue that respond to the environment and enables animals to sense
- 14. muscle type of tissue in internal organs and blood vessels; voluntary
- 15. carry their young in a pouch--kangaroo
- 18. atria receives deoxygenated blood from the vena cava
- 19. valve atrioventricular valve found between the RA and RV
- 21. arteries bring blood to the lungs; only artery to carry deoxygenated blood
- 23. ventricle sends blood to the aorta and rest of body
- 24. veins brings blood to the LA or heart; only vein to carry oxygenated blood