INTERESTING FACTS:

Sharks have the most powerful jaws on the planet. Unlike most animals' jaws, both the sharks' upper and lower jaws move.
A shark bites with it's lower jaw first and then its upper. It tosses its head back and forth to tear loose a piece of meat which it swallows whole.

Each type of shark has a different shaped tooth depending on their diet
Sharks never run out of teeth. If one is lost, another spins forward from the rows and rows of backup teeth.

Normally, sharks eat alone. But sometimes one feeding shark attracts others. They swim up as quickly as possible and all begin to try to get a piece of the prey. They bite wildly at anything that gets in their way -- even each other.
The great white shark rarely partakes in feeding frenzies.

Almost all sharks are "carnivores" or meat eaters. They live on a diet of fish and sea mammals (like dolphins and seals) and even such prey as turtles and seagulls.
"Sharks even eat other sharks. For example, a tiger shark might eat a bull shark, a bull shark might eat a blacktip shark and a blacktip shark might eat a dogfish shark.
The teeth of the carnivores are sharp and pointy. Their skeleton is made of cartilage instead of bone, which allows greater flexibility." (Martin 10)

"Their skin is made of denticles instead of ordinary fish scales. The denticles are constructed like hard, sharp teeth and help to protect the shark from injury." (Martin 15)

Not all sharks are fierce carnivores. Some are quite harmless. Oddly enough, the most harmless sharks tend to be the largest! The basking shark, the whale shark and the megamouth sharks all fit this description.

These huge sharks eat plankton, a tiny shrimp-like creature found in the ocean. To do this, they swim forward with their mouths wide open. "Gill rakers" at the back of their throat strain the tiny food from the water.

Baby sharks are called pups. Just like there are many types of sharks, there are also different ways that sharks come into this world. There are three ways that sharks are born:

eggs are laid (like birds)
eggs hatch inside the mother and then are born
pups sharks grow inside the mother (like humans)

Sharks can have from 1 to 100 babies at a time, depending on the type of shark. The ones with pups that grow inside the mother have fewer babies at a time than sharks that lay eggs outside the body.

Sharks do not care for their babies after they are born, but they do search for a safe place where they can lay their eggs or give birth.

Sharks and rays do not have true bones like other fishes. They have cartilage instead which is lighter and much more elastic and allows them to bend in very tight circles.

Sharks have an extra sense that is able to detect tiny electric fields. They can use this to find food that is buried or search for animals to eat in the dark or in turbid water.

Works Cited

Digest, Reader's. Sharks. New York: n.p., 1998. 

Haven, Kendall. Wonders of the Sea. Monterey, CA: Challengers, 2005. 

Live Science. 4 Apr. 2008 . 

Shark Trust. 4 Apr. 2008 .