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Sharks - Free Sample

To begin with, it's the skeleton that makes a shark a shark. It consists of cartilage rather than bone, therefore forming its own class of cartilaginous fish (Elasmobranchii) together with the ray and the likewise related chimeras. The cartilage is strong, durable, yet flexible and lightweight at the same time. Therefore, sharks do not need an air bladder that would have to balance out the weight of heavy bones. The lack of buoyancy is compensated in part with a large, high fat liver, which also serves as an energy storage unit. Another advantage: Without an air bladder, sharks do not de-velop pressure problems during fast hunting through different depth zones. Moreover, their spinal column flexibility permits hunting sharks to swim very close circular radii, much to the fatal disad-vantage of their rigid boned prey. Everywhere where larger forces within the shark's lightweight skeleton prevail, reinforcement takes place by storing calcium within the cartilage, thus achieving bone strength but without the extra weight. © K. Bars Introduction Sharks


Sharks - Free Sample
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