When a mussel is exposed to a chemical irritant such as crude oil, certain genes respond, triggering mRNA to carry a message to the mussel’s cells. That message tells the cells how to deal with the irritant. Every irritant triggers a different pattern of genes. The scientists looked for the genetic and chemical response patterns unique to crude oil.
Their analysis showed that both oil concentrations and gene response spiked then decreased with time, however the genetic response peaked at a later time.
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