A '''memory cell''' is a group of cells that help the body defend itself against [[disease]] by remembering prior exposure to specific organisms (e.g. [[viruses]] or [[bacteria]]). Therefore, these cells are able to respond quickly when these organisms repeatedly threaten the body.<ref>http://www.cdc.gov/vaccines/about/terms/glossary.htm#m</ref>
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A '''memory cell''' is a group of cells that help the body defend itself against [[disease]] by remembering prior exposure to specific organisms (e.g. [[viruses]] or [[bacteria]]). Therefore, these cells are able to respond quickly when these organisms repeatedly threaten the body.<ref>https://www.cdc.gov/vaccines/about/terms/glossary.htm#m</ref>