- At the front of the shark and behind its head, are the pectoral fins. Sharks use these fins to lift and gudie the shark as they swim.
- The pelvic fins keep the shark stable as it swims. In boy sharks the pelvic fins are used as claspers, which are helpful for the reproduction process.
- The skeleton of a shark is mainly cartilage. The sharks have at least 230 bones. Cartilage is flexible and durable, yet has about half the density of bone. This reduces the skeleton’s weight, saving energy. The shark has no rib cage, therefore on land a shark can crush itself.