body. The brain can also send signals through the nerve fibers to control the activities of the body.The Great White(Carcharodon carcharias)The great white shark is a ferocious predator. This species of shark comes in a variety of sizes, but average about 4.3 to 5.5m. Roughly they weigh about 680 to 1,800kg. The great white shark is equipped with extraordinary senses. They primarily use their sense of smell, followed by their sensing of electric charges. Other senses such as eyesight, sensing changes in water pressure and hearing are seldom used. the great white's nostrils can smell a single drop of blood in 25 gallons of water. The sensing of minute electrical discharges in the water is accomplished by a series of jelly-filled canals in the head called the ampullae of Lorenzini. This allows the shark to sense the tiny electrical fields generated by all animals, for example, from muscle contractions. It may also use this to detect magnetic fields which some sharks may use in navigation. To compliment its senses, it is also an amazing swimmer. Equipped with a stream-lined body which allows it to may reach speeds of up to 40 mph. It has 3 primary fins, the dorsal fin(on its back) and 2 pectorial fins; however the great white shark does not use these while swimming. It swims by propelling itself through the water by using its tail. One negative aspect of the shark is its inability to bend its pectorial fins backward. This prevents it from stopping suddenly or swimming backward. A shark must keep swimming or it will sink. Perhaps the most feared part of the great white is its mouth. The sharks mouth is supplied with a huge amount of teeth at one time(up to 3,000). They are triangular, serrated, razor-sharp and up to 3in long. These teeth are located in several rows which rotate into use as needed. The first two are used in obtaining prey. As this teeth get worn of break, some from the back rows rotate into the front. T...
