The shark is...

The shark is the representative of the mammals that is very spread in many seas and oceans of the world. There are about 350 species of sharks. And there are also some sharks that live in the freshwater basins. The majority of species is referred to the real predators, but there are also some species that prefer plankton to the bloody meat. The view of the shark is probably known to everybody even if the person has never seen it in reality. This fact can be explained by numerous films that describe and show different kinds of the sharks. So, these inhabitants of the sea have log body and a lot of teeth.

Five-seven and sometimes even ten branchial fissures are characteristic for sharks. Their number depends on the species of the shark. Sharks have the possibility to breathe under the water thanks to them. There is a lot of information in the internet that sharks need to move to breathe. This holds true only for a few sharks.

The majority of sharks are cold-blooded animals. The temperature of their body corresponds to the temperature of the environment. However some species of sharks are the exception from the rule (there are about 8 species in total). These species are partially warm-blooded and may have the temperature of the body 8-11o C more than the temperature of the environment because of the intensive work of the muscular system.

It is interesting to know that sharks regularly release their stomach through the mouth into the water. In such way they clear it. And the stomach is never hurt by the numerous teeth of sharks.