1.
Skeletons are composed of this material
2.
A tail that has two lobes of equal size and provide forward thrust
3.
The bony gill covering on some fish
4.
What fish use to collect underwater sensory information
6.
Each of the thin plates that make up the gill filament of a fish.
7.
Calcareous ear stones that fish use to detect change in the body position.
8.
One of several sensory structures in the head of sharks that detect weak electrical fields(three words)
9.
A gas filled sac that allows the fish to adjust buoyancy (two words)
10.
Marine fish that migrate to freshwater to breed
11.
Freshwater fish that migrate to the ocean to breed
12.
An animal that releases eggs
13.
An animal that produces eggs that hatch inside the female immediately before birth.
14.
An animal whose eggs develop inside the female while the embryo drives nutrition from the mother directly from the womb or by a placenta, as in most mammals.
15.
The organ in fish responsible for oxygen-carbon dioxide exchange
16.
The process that allows fish to prevent dehydration in a salt environment
17.
A substance that dissociates in water into charged particles called ions.
18.
How an organism can maintain more or less constant internal conditions that allow it to adapt and to survive in the face of a changing and often hostile external environment.
