BIOL 1201 : Final
Document Summary
Used to be living things (parasites) and relied heavily on the host. They became non- living over time: stripped-down versions of previously living cells, viruses arose before, at same time, or shortly after life began on our planet. Viral replication: steps, find cell bind to cell replicate in the cell exit the cell, lytic cycle. Infect host cells and the viral dna: every time the host cell divides, the viral genome also replicates, the cell receives signals to enter the lytic cycle (after a period of dormancy) and the virus is spread, picture. Table with different classes of viruses: chicken pox uses double-stranded dna, doesn"t mutate because dsdna is replicated carefully with out own enzymes, hiv uses single stranded rna to make dna. Influenza uses single stranded rna to make mrna: mutates because viral proteins replicate the rna and no repair enzymes are there to fix it or proofread the sequence.
