SCIENCE
VIRUS AND BACTERIA
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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True
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False
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Either A or B
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None of the above
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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: -Answer and Explanation: All of the following are true of a lysogenic replicative cycle execpt for that the host cell must die as a result of the infection. The host cell does not die but it’s chromosomes become copied along with the phage’s DNA and gets passed on to new daughter cells during reproduction.
Detailed explanation-3: -A lysogenic cell contains viral DNA, a prophage, integrated into the host chromosome. The integration of phage DNA into host DNA occurs in much the same fashion as seen in transformation, transduction or conjugation. Filamentous virus is incapable of causing a lytic infection.
Detailed explanation-4: -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.