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Unformatted text preview: Chapter 18 Adolf Mayer- experimented with leaf diseases by rubbing sap onto healthy ones infecting them directly; concluded small bacteria Wendell Stanley- after scientists clung to hypothesis that bacteria caused disease, Stanleycrystallized the TMV, electron scope helps Virus- not truly live; need host to live- obligate intracellular parasites ; made of DNA/RNA and protein coat or membranous envelope a. Capsid- protein shell enclosing viral genome (i.e. polyhedral or rod shaped) b. Capsomeres- protein subunits that make up capsid c. Viral Envelopes- accessory part that helps infect host cell by taking cells membrane viruss membranous envelope d. Lack metabolic enzymes, ribosomes, and other equipment for protein synthesis; can only infect host cell Bacteriophages/Phages- have most complex capsids; has various types that infect E. Coli (T1, T2, T3, T4, T5) Host Range- the limited range of host cells a virus can infect; due to lock-and-key structure of virus and specific receptors of host...
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- Spring '10