DNA and Complete Metamorphosis
Location: Outside U.S.
Date: Winter 2011-2012
I have read the question about the butterfly life cycle. It says the DNA of a butterfly and caterpillar are the same, well that's how I read it. I would like to know the exact cycle of a caterpillar to butterfly. I thought egg,caterpillar,chrysalis,red liquid (DNA soup!) body,out,dries wings strange liquid oozes out... As biology says it when ever you change your DNA will be the same...But as butterfly experts say they DNA from a caterpillar and the same butterfly is complete different. So next question is this true?
My question to you is: if you want a recipe for chocolate chip cookies, do you need to read the whole cookbook? Or do you just go to the recipe for the cookies and ignore the rest? The caterpillar's cells and the butterfy's cells both contain the same instruction manual (DNA) but they read different parts of it at different stages of their life cycle.
Your lifecycle is correct! The DNA is the same for all life stages, but what differs is the expression of that DNA.
Think of DNA as a digital mixer - like the one used by DJ's. This mixer is a bunch of switches that are turned on or off as needed. This ensures that the proper tracks play during the course of the song (the "song" is the development of the organism, from egg to adulthood!) When no longer needed at a point in the song, a switch is turned down and fades. Then a different switch is turned on and the volume might be maxed out. Every life stage is a new genetic remix - all the options are available at a given time, but only certain ones are in play at a given time.
Dr. Tim Durham
Undergraduate Studies & University Colloquium
Department of Biological Sciences
Florida Gulf Coast University
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Update: June 2012