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Name: Jenny
Status: Student
Grade:  6-8
Location: AK
Country: United States
Date: April 2005

Is there a relationship between the concentration of phosphate ions in nutrient solutions and the number of cells dividing by mitosis in root tips?

I'll give you a hint-anything an organism can do (ie, a function) is usually as a result of protein-protein interactions, and proteins are coded for by genes, and genes can change over time..... By the way-it isn't necessarily true that Legionnella pneumophila hadn't been pathogenic before that time-it just hadn't been described up until that point. After the outbreak, many samples of tissue from people who died from pneumonia of unknown cause were re-examined and found to be carrying this organism. Mystery solved.


This bacterium may have never become pathogenic without the advent of air-conditioning so it wasn't necessarily the bacterium changing by a new ecological niche opening up for this organism.

Ron Baker, Ph.D.

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