Sharks
Sharks are commonly defined as a marine fish of the order Squaliformes or Selechii. They make up the Chondrichthyes, or “cartilaginous fish” along with skates, rays, and a few other fish. Members of the Chondrichthyes lack true bone and have a skeleton made of cartilage. Only their teeth, and sometimes their vertebrae, are calcified, but this is still not true bone. The bone structure is one of the main differences that separates sharks from other fish and marine animals. Sharks also differ in that they have a skull without sutures and reserve rows of teeth attached to the skin of the jaws. They lack an air bladder forcing all but shallow-water forms to swim constantly in order to keep from sinking. When looking at sharks there are eight orders and about 350 species so it is difficult to discuss each one in detail. All sharks are Selachians and are characterized by a fusiform body with five to seven pairs of lateral gill slits. Sharks are easily identified by distinctive characteristics such as a ventrally positioned mouth, an asymmetrical tail with the vertebral column extended into the upper lobe, and a body covered with tiny, sharply pointed placoid scales. Sharks are found at all depths of all the oce
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Some common words found in the essay are:
Selechii Chondrichthyes, Sharks Sharks, bony fish, true bone, eggs develop, gill slits, species species,
Approximate Word count = 1084
Approximate Pages = 4 (250 words per page double spaced)
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