What is it A virus is basically a

What is it? ? �A virus is basically a piece of nucleic acid (DNA or RNA) encased in a tough outer covering of protein �Viruses ≠ Bacteria Viruses are so small, they make bacteria look big!

NOT Living! �Viruses DO NOT: NOT Reproduce Use energy Grow Have cell parts like organelles or cytoplasm Have cells �Therefore NOT LIVING No Classification with the living organisms

What do they look like? ?

Types of Viruses � Some human viral diseases include: HIV AIDS Measles Chicken pox Mumps Colds Polio Cold sores Rabies Influenza (flu) Smallpox Ebola Warts

What are they made of? ?

What do they do? ? �Viruses may infect eukaryotic cells like ours or they could infect a bacteria! bacteria First they attach to the host cell Then they inject their little piece of nucleic acid into the cell 3. That nucleic hijacks the cell’s DNA and turns it into a virus factory making only virus parts! parts 1. 2.

Infected… The result… �Cells fill up with viral pieces and EXPLODE spreading the viruses �Sometimes infection will happen immediately �Some stay latent or dormant for years

Offensive & Defense DEFENSIVE/PREVENTATIVE � Vaccine – a weakened form of the virus � Vaccination – giving vulnerable animals a vaccine to alert the immune system to the structure of the pathogen � Good hygiene – practicing constant cleaning People Food OFFENSIVE � Antibodies – proteins that attach to virus and alert WBCs to eat it! � Interferon – chemical interferes with the manufacture of virus parts in an infected cell and noninfected cell � Immune Response – bodies police force

Additional Questions about Viruses? �