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Name: William H
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Hi! We are a second grade class at Frank C. Whiteley School in Palatine, Illinois. We are currently studying ponds and found a neat butterfly at a pond. We would like to know what is in a cocoon that makes a caterpillar turn into a butterfly? Please answer our question soon because we are anxious and hopeful that a scientist out there cares about us!!!!! You are a nice scientist for answering our question. We will send you a nice thank you note if you answer our question.

There is nothing inside the cocoon that makes a caterpillar turn into a butterfly. It is a chemical inside the caterpillar. This chemical is called a hormone and cells inside the caterpillar make it. How does the caterpillar know when to do this?? Nobody knows for sure!


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