Viruses

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Viruses
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Characteristics of Viruses

• Nonliving particle made up of nucleic acid
  protein
• Nonliving because lack some characteristics of
  life
• Cause many diseases in living organisms
• Contain genetic information
• Cannot reproduce outside a hosts cell

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Characteristics of Viruses

• Vary in size and shape
• Helix
• Rabies and measles viruses
• Icosahedron
• Warts, cold sores, herpes simplex chicken pox,
  polio and small pox viruses
• Spherical
• Influenza

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Viral Replication

• Lytic Cycle
• The virus attaches cell
• Injects its DNA
• Takes control of the host
• New viruses are made
• Cell lyses
• Releases the viruses

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Viral Replication

• Lysogenic Cycle
• Enters the same as Lytic
• DNA integrates with the
• host cells DNA
• Host cells cell replicates
• Enters the lytic cycle

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