Biology 1202B Lecture Notes - Lecture 22: Lysosome, Chromosome, Prophage
11 Apr 2016
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Document Summary
Viruses: small infectious agents that replicate inside living cells of other organisms (therefore not considered alive) Dna or rna genomes with protein coat surrounding. Protein coat: comprised of repeating protein subunits (small genome) Coat may be surrounded by "envelope" from host cell, though it is still not considered a cell o. This "envelope" contains both host and viral proteins and aids entry into cells i. e. hiv. Virulent bacteriophage (kill host cell with every infection cycle) Temperate bacteriophage: may enter inactive phase and this information is passed on to daughter cells. Phage not mobile (must collide at random with host cell) Phage enzyme lysozome (creates a hole in bacterial cell wall) Phage uses the host cell"s ability to transcribe and translate its genes. o. Phage may contain its own polymerase and can recombine (leading to a high rate of evolution) Phage enclosed lysozome (to break out of cell and release progeny phages) Infection: phage attaches to bacteria and injects its dna.
