The viral genome is known as provirus or prophage in

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The viral genome is known as provirus or prophage (in the case of bacteriophages ). bacteriophage : a virus that specifically infects bacteria. Whenever the host divides, the viral genome is replicated Bacteriophages may have a lytic or a lysogenic cycle. Lysogenic cycle : a form of viral reproduction that involves fuses the nucleic acid of a bacteriophage with a host, followed by the multiplication of the resulting prophage. (See Fig. 3). Infects the host cell genome from within. Phage DNA is joined with the host genome, where it is passed on to the next generations. This cycle does not result in immediate lysing of the host cell.
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HOME ASSIGNMENT #1 5 Phages that go through lysogeny are called temperate phages, The viral genome integrates with host DNA and replicates. Sometimes becoming a plasmid . The virus remains dormant until host conditions degenerate due to lack of nutrients. Then the prophages become active starting the reproductive cycle, resulting in lysis of the host cell. The lysogenic cycle allows the host cell to continue to survive and reproduce and the virus is reproduced in all of the cell’s offspring. An example of a bacteriophage is the phage lambda of E. coli. Lytic cycle: the normal process of viral reproduction involving entering the cell membrane, nucleic acid synthesis, and lysis of the host cell. (See Fig. 3). The phage replicates and lyses the host cell . Bacterial cells are broken open and destroyed after immediate replication of the virion. Once the cell is destroyed, the phage progeny can find new hosts to infect. Example of lytic bacteriophage is T4. Infects E.coli found in human intestinal tract. Some lytic phages experience lysis inhibition that happens when the completed phage progeny will not immediately lyse out of the cell if extracellular phage concentrations are high.
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