animal

3. dependent on or capable of the internal generation of heat.
5. a gas-filled organ in fish that helps them control buoyancy, allowing them to maintain depth in the water without sinking or floating
9. - type of symmetry where an organism or object can be divided into similar halves by many different lines that intersect at a central point, like a pie or a whee
10. type of invertebrate animal characterized by the following features
11. the bottom of a body of water, such as an ocean, lake, or stream
12. to the free-swimming, umbrella-shaped body form of certain cnidarians, like jellyfish, that contrasts with the sessile polyph form
14. hard, external covering that provides support and protection for many invertebrate animals,
16. - modified sweat glands that produce and secrete milk for lactation in mammals.
18. -an organism that possesses both male and female reproductive organs or tissues,
19. a form of asexual reproduction that results from the outgrowth of a part of a cell or body region leading to a separation from the original organism into two individuals.
20. relies on external sources of heat to regulate its body temperature
21. internal skeleton, such as the bony or cartilaginous skeleton of vertebrates

1. -the property of being divisible into symmetrical halves on either side of a unique plane.
2. an animal of a large group distinguished by the possession of a backbone or spinal column
4. A tough, flexible tissue that lines joints and gives structure to the nose, ears, larynx, and other parts of the body
6. a unique hydraulic system found in echin
7. loss of plumage, skin, or hair
8. a temporary disc-shaped organ that develops in the uterus during pregnancy and connects the developing fetus to the mother's blood supply
13. a type of egg laid by reptiles, birds, and some mammals
15. lack of equality or equivalence between parts or aspects of something
17. animals that neither develop nor retain a vertebral column which evolved from the notochord