Across
- 3. an animal with a backbone
- 5. the shedding or casting off of an outer layer or covering and the formation of its replacement
- 6. having both male and female reproductive organs
- 8. gas-filled sac present in the body of many bony fishes, used to maintain and control buoyancy.
- 10. an internal skeleton
- 11. an animal lacking a backbone
- 15. any animal whose regulation of body temperature depends on external sources, such as sunlight or a heated rock surface
- 16. type of egg produced in which
- 18. symmetry around a central axis
- 21. the property of being divisible into symmetrical halves on either side of a unique plane.
- 22. form of cnidarian in which the body is shaped like an umbrella
Down
- 1. a network of water vessels in the body, the tube feet being operated by hydraulic pressure within the vessels.
- 2. soft tissue in some animals
- 4. asexual reproduction where an organism detaches a part of itself
- 7. rigid external covering for the body in some invertebrate animals, especially arthropods, providing both support and protection
- 9. organisms who live at the lowest level of a body of water such as a lake or ocean
- 12. embryo develops inside the amnion
- 13. organ that develops in uterus during pregnancy
- 14. dependent on or capable of the internal generation of heat.
- 17. tiny, soft-bodied organisms related to sea anemones
- 19. the milk-producing gland of women or other female mammals
- 20. no pattern or symmetry