If shark extract of water, it will be crushed by its own weight

Sharks - being very zagadochnye

shark skeletons are very different from the skeletons of bony fishes and land vertebrates. Their skeleton made of cartilage and connective tissue, which means that they cartilage. The fact that this reduces the weight of the shark skeleton means that a shark saves energy.

Sharks do not have chests to protect their internal organs, and when they find themselves out of the water, they are very easy to be crushed themselves by their own weight. When they are in the water, the buoyant force acting against their weight, and does not allow it to happen.

Sharks do not have gas-filled swim bladder for buoyancy as other fish, and therefore must use their pectoral fins as well as the aircraft using their wings. This is called "dynamic lift". When they swim, they have their fins in a certain way in order to create a lifting force that allows them to stay at a certain depth.

There is a myth that sharks must keep moving in order to breathe, but in fact they have to keep moving to stay afloat, since they have no swim bladder. For the same reason, they are not able to go back, or hang on the spot. In moments of rest, most sharks pumped water through the gills to ensure a constant flow of water saturated with oxygen.

via factroom.ru