Which step(s) of the viral life cycle would most likely occur in lytic phages?Injection of viral genetic material into the bacterial hostIntegration of viral DNA into the bacterial genomeDegradation of the host genome

Question

Which step(s) of the viral life cycle would most likely occur in lytic phages?Injection of viral genetic material into the bacterial hostIntegration of viral DNA into the bacterial genomeDegradation of the host genome

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11ecba2d_0fd1_b978_a3bf_afae43108a3b_MD0008_00 All viruses are obligate intracellular parasites because they cannot replicate independently outside of a host cell. Bacteriophages are viruses that exclusively infect bacteria. The life cycle of a particular bacteriophage can be lytic or lysogenic, which will determine the method by which the phage uses the host's cellular machinery to create new progeny. The general steps involved during the lytic life cycle are described as follows: Attachment: The bacteriophage comes in contact with the bacterial cell wall and attaches to the host bacterium using its tail fibers. Viral genome entry: The phage uses its tail sheath to inject its genome into the cytoplasm of the bacterial host (Number I). Host genome degradation: Viral enzymes degrade the host genome into its nucleotide components to provide the building blocks for replication of the viral genome (Number III). Synthesis: Loss of the bacterial chromosome ends synthesis of host molecules. As a result, the host machinery (eg, ribosomes), now under the control of the viral genome, begins to synthesize the components needed for new viral progeny, which then assemble inside the host cell. Release: Many newly assembled viral progeny (virions) are released as the bacterium disintegrates (lysis) due to the action of lysozymes on the host cell wall. (Number II) In contrast, bacteriophages that have a lysogenic life cycle also attach to the bacterium but integrate their genome into the host DNA and are called prophages. This viral genome integration enables the host cell to survive and divide normally. While the host cell divides, the integrated viral DNA is replicated with the host DNA, and associated viral repressor proteins prevent the viral genome from being transcribed (latency). Induction can occur in response to environmental factors (eg, chemicals, radiation), causing the viral genome to excise itself from the host chromosome and enter the lytic life cycle. Educational objective: Bacteriophages use the host cell's machinery and resources to replicate their genome and synthesize viral proteins to form new virions. Phages with a lytic life cycle replicate rapidly and release progeny via lysis of the host cell. In contrast, phages with a lysogenic life cycle integrate their genome with the host genome and replicate as the cell divides.

Which Step(s) of the Viral Life Cycle Would Most Likely Occur