Bacteria are living cells with DNA. They replicate on their own.

Viruses are small particles of DNA or RNA and need a host cells to reproduce.​

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​Viruses are different than bacteria

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Viruses have RNA inside of the capsid. The capsid is surrounded in an envelope of protein spikes.

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​Virus Structure

Viral spikes attach to receptors on the cell and trick the cell into letting it in.

​Viruses use spikes to enter cells.

virus life cycle

T-cells attack infected cells in the body. They recognize infected cells by the viral spikes on the cell membrane.

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​T-cells

B-cells recognize viruses or ciral parts outside of the cell. They make antibodies to fight the infection. They have a memory system.

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​B-cells

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