Topic 8: intro to virus

poison

latin word for virus

electron microscope

what invention made it possible to see viruses?

adolf mayer

first describe tobacco mosaic disease could be transferred between plants

Dmitri ivanovski

showed that infected sap remained infectious even after filtering through the finest chamberland filters

martinus beijerinick

also demonstrated the filteribility of the agent; realized that the disease could be used for serial transmission of disease without loss of potency

loffler and frosch

identified the first filterable agent from animals, the virus of FMD

20 to 300nm

size of the virus

viruses

• an obligatory intracellular parasites meaning they require living host cells in order to multiply

• have few or no enzymes of their own for metabolism. Thus, to mutiply, they must take over the metabolic machinery of the host cell

host range

• virus is the spectrum of the host cells the virus can infect

• viruses that infect invertebrates, vertebrates, plants, protists, fungi and bacteria

plasma membranes

for animal viruses, the receptor sites are on ______.

virion

a complete, fully developed viral particle composed of nucleic acid surrounded by a coat

capsid

• the protein coat surrounding the nucleic acid of a virus

• is composed of subunits which can be a single type of protein or several types

capsomeres

a single type of protein or several types

bacteriophages

aare the easiest viruses to grow