Sharks are a group (superordo Selachimorpha) fish with a complete cartilage skeleton and a slender body. They breathe using gills burrow five (sometimes six or seven, depending on the species) in addition to, or beginning slightly behind, his head. Sharks have skin-covered body dermal denticles to protect their skin from damage, from the parasite, and to increase the dynamics of water. They have several rows of teeth can be replaced.
