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Bony Fish

   A Bone to Pick

phytoplanktonBony fish come in all kinds of shapes, sizes and colors, but they all have some things in common. There are over 20,000 species of fresh and salt water bony fish. All bony fish have skeletons made of bone. Most of them have a swim bladder or air-filled sac that helps them float. Bony fish are covered in scales and they have gills on the sides of their heads.

 
    Getting Some Air
phytoplanktonFish use air, but they do it in a different way than land animals. Fish pull water into their mouths and then pump the water over their gills. Their gills absorb oxygen from the water into gill membranes, then the oxygen passes into the fishes' blood stream.
    Fin Fun
FishFish have a variety of fin types that help them swim. Most fish have a caudal or tail fin, a dorsal fin on their back and pectoral fins on their sides. Most fish also have a lateral line on their sides. The lateral line is a fluid-filled tube that helps fish sense movement. This can help them avoid predators and find prey! 

 


 


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