BIOL 211 Lecture Notes - Lecture 28: Blood Transfusion, Bacteriophage, Antibiotics
Document Summary
Week 14 - lecture #21 viruses, viroids, and prions. Martinus willem beijerinck: dutch microbiologist and botanist. Some viruses have a lipid membrane or envelope. Icosahedron: new shape with 20 equilateral triangular faces. Enveloped (membranous): nucleocapsid + spikes + membrane. Retroviruses go against the central dogma [rna dna rna protein] (+) rna strand (positive-polarity rna viruses) (mrna) (-) rna strand (negative-polarity rna viruses) (complement to mrna) All viruses must: attach to host cell, get viral genome into host cell, replicate genome, make viral proteins, assemble capsids, release progeny viruses from host cell. Injected linear phage dna circularizes and enters lytic or lysogenic cycle. Prophage is integrated into the bacterial chromosome. Replication of phage dna and synthesis of phage-encoded proteins. Viruses do not want to kill their host. Viruses can have dna or rna in their genome. This is the factor that determines a virus. Eradicated in 1979 - best example of who fight against viruses.