|MadSci Network: General Biology
Hi Danielle, There are many kinds of molds that would love to grow on the three foods you have listed. There could be several reasons that you saw faster growth on your orange. The main reason would probably be that the bread and cheese contained preservatives. These are usually added to bread and cheese for the purpose of preventing or retarding mold growth. If you did this experiment again, you would want to choose a bread and a cheese which did not contain preservatives such as priopionates or sorbates. Other reasons for the faster growth on the orange could be that the particular type or species of mold on the orange had a faster growth rate than the molds on the bread and cheese - that is if they were all different species. Other factors to consider would be the moisture contents of the bread, cheese, and orange skin and the temperatures that these were held at. I hope that answers your question.
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