Fishes

6. producing young by means of eggs which are hatched within the body of the parent
7. a method of camouflage in which an animal's coloration is darker on the upper side and lighter on the underside of the body.
8. a form of discoloration that is used to disguise an animal's shape
12. bringing forth live young that have developed inside the body of the parent.
14. a gas-filled sac present in the body of many bony fishes, used to maintain and control buoyancy.
16. a sensory organ of fishes and larval or aquatic amphibians, typically forming part of the lateral line system
17. the word for the tiniest form of shellfish that has settled onto the place where it will live out its life
18. A stage in the life cycle of a veliger when it is able to crawl using its foot.
19. bony fish

1. an iron- and oxygen-binding protein found in the skeletal muscle tissue of vertebrates in general and in almost all mammals.
2. jawless fish
3. group of fish is swimming in the same direction in a coordinated manner
4. migrating from fresh water to saltwater to breed
5. cartilaginous fish
9. an aquatic mollusk that has a compressed body enclosed within a hinged shell, such as oysters, clams, mussels, and scallops.
10. migrating from saltwater to freshwater to breed
11. a structure that covers the gills
13. the final larval stage of certain mollusks, having two ciliated flaps for swimming and feeding.
15. system of tactile sense organs that detect movements and pressure changes in the water
20. any group of fish that stay together for social reasons