Animal Crossword

3. Bladder A gas-filled internal organ that helps bony fish control their buoyancy.
9. An animal that lacks a backbone or vertebral column.
10. Symmetry A body plan divisible into two mirror-image left and right halves.
11. A body plan with no balanced arrangement or lines of symmetry.
15. The free-swimming, umbrella-shaped body form of a cnidarian.
20. Able to maintain a warm body temperature through internal metabolic heat.
21. An internal skeleton or support framework inside an animal's body.

1. A tough, flexible connective tissue that supports structures or forms skeletons in fish like sharks.
2. Eggs Shell-covered eggs with protective membranes that allow embryos to develop safely on land.
4. An animal that possesses a backbone or spinal column.
5. Vascular System A network of hydraulic canals used by echinoderms for movement and feeding.
6. An organism possessing both male and female reproductive organs.
7. Relying on external environment sources to regulate body heat.
8. To process of shedding an outer shell or exoskeleton to allow growth.
12. Glands Specialized organs in female mammals that produce milk for offspring.
13. An organ in pregnant mammals that supplies oxygen and nutrients from mother to fetus.
14. A form of asexual reproduction where a new organism grows out from the parent.
16. A hard, protective outer covering found on arthropods.
17. Relating to or living at the bottom of a ocean or body of water.
18. Symmetry Body organization arranged around a central axis like spokes on a wheel.
19. The sessile, tube-shaped body form of a cnidarian.