Introduction Sharks are one of the most fearsome sea animals. They live in oceans across the world, but are most common in tropical waters. There are more than three hundred fifty species of sharks. The hammerheads are classified as Chondrichthyes, because they are jawed fish with paired fins, paired nares, scales, a heart with its chambers in series, and skeletons made of cartilage instead of bone. There subclass is Elasmobranchii because they have five to seven pairs of gills, rigid dorsal fins…
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