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Name: Marta
Status: Educator
Grade:  6-8
Location: NY
Country: United States
Date: April 2005

I am a 6th grade science teacher at a public middle school in Brooklyn and my students and I have a burning question! We just made wet mount slides with onions using iodine. we know that the iodine reacts with starchy molecules in some organelles, so we saw the cell wall darker but in some of the cells, many of them we saw towards the corners of the cell , next to the wall a darker circular shape. I thought it was the nucleus, but honestly I don' t think it is and can' t figure out what it is!!!! Please help!

My guess is that they are starch granules used by the cell to store energy in the form of starch.

Ron Baker, Ph.D.

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