Monday 8 August 2011

Characteristic Of Crab.

About crab....

          Imagine that you are tanning in the sun, and you feel something nibbling at your toes. You look down and see a ton of little red creatures at your feet. You have no clue what they are. Then, you get a closer look at one of them, and you notice they are crabs. You don’t notice one of the crabs has been climbing up your chair. Before you notice it is there, it bites you. 

         A crab is a small sea creature. Crabs live in shells and they don’t move very fast. All crabs have eight walking legs and two claws. There are about 45,000 types crabs that come in many different kind of colors.Some crabs live on land and others live in the water. The crabs that live in the water have paddles on their back legs. This is what makes them able to swim. Crabs that live on land have eight walking legs which are on the backside of the crab’s body make the crab walk either right or left. One side of the 8 back legs helps pull the crab, and the other four stretch out and push. The crab doesn’t move straight forward.
       
   During the first stage, the crab is known as a zoea. The zoea is very tiny and looks a lot like a shrimp. When the crab is a zoea, it is usually about 1 millimeter (1/ 25 inches) long. The zoea usually feeds only on the larvae of oysters and starfish. The zoea starts to shed the outer layer of its shell because it is getting big. This is called molting.During the final stage, the crabs are full grown. The megalops on the crab molts. Then a young crab has all of the body parts that an adult crab has. The hard part that gets made during this process is called a chitin. A chitin is the hard part of the crab also known as a carapace. When the crab grows, the chitin grows with it. The chitin stays with the crab for its whole life.

7 comments:

  1. Nice. I don't know that there are 45 thousands of varieties of crabs. Glad to know that.thanks.

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  2. Nice. I don't know that there are 45 thousands of varieties of crabs. Glad to know that.thanks.

    ReplyDelete
  3. Crabs do not bite. They pinch.

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  4. Crabs do not bite. They pinch.

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  5. anybodt to explain about fertization in crabs

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