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Life needs to be able to make different proteins at different times.
For example, if its food changes it will need to make different enzymes . So it must be able to turn messages on and off, so that the right proteins can be made in the right amounts at the right time. Life does this by storing the information for each message in a different kind of nucleic acid molecule called a gene. A gene contains two molecules of nucleic acid which fit together very closely. The gene's information is hidden with its bases buried inside the gene.