SCIENCE
VIRUS AND BACTERIA
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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The viral DNA enters the host.
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A virion is produced.
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Viral DNA becomes injected into the host cell.
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Viral DNA joins with host cell DNA to create a prophage (provirus).
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Detailed explanation-1: -The lysogenic cycle: The phage infects a bacterium and inserts its DNA into the bacterial chromosome, allowing the phage DNA (now called a prophage) to be copied and passed on along with the cell’s own DNA.
Detailed explanation-2: -In lysogenic infection, viral DNA gets integrated with the host cell’s DNA, where it is copied along with the host cell’s DNA when the host cell replicates. Viral DNA multiplies as the host cell multiplies. Each new daughter cell created is infected with the virus’ DNA.
Detailed explanation-3: -Lysogeny is characterized by integration of the bacteriophage nucleic acid into the host bacterium’s genome or formation of a circular replicon in the bacterial cytoplasm. In this condition the bacterium continues to live and reproduce normally, while the bacteriophage lies in a dormant state in the host cell.
Detailed explanation-4: -In the lytic cycle, the phage replicates and lyses the host cell. In the lysogenic cycle, phage DNA is incorporated into the host genome, where it is passed on to subsequent generations.
Detailed explanation-5: -However, every time the host cell reproduces, the provirus is replicated along with the host cell’s chromosome.