What Are Fish?
A fish is a cold-blooded animal which is also a vertebrate (animal with a backbone). They are aquatic vertebrates; they have gills and fins and they also live in water their entire lives. This is what makes fish different from other types of animals in the world. There are a few exceptions to the cold-blooded rule for fish. New fish have been discovered that are completely warm-blooded.
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How fish breath under water?
Fish have gills which are apart of them since the moment they are born. Gills give fish the ability to breath … Continue