The key differences between the lysogenic and lytic cycles are as follows:
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Host Cell Destruction: The host cell is destroyed during the lytic cycle, whereas in the lysogenic cycle, the host cell survives for an extended period as the viral DNA integrates into the host's genome.
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Viral DNA Injection: In the lysogenic cycle, the virus injects its DNA into the host cell, which then becomes part of the host's genetic material (prophage). In the lytic cycle, the viral DNA is injected and immediately begins to hijack the host's machinery to produce new viruses.
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Host Cell DNA Replication: During the lytic cycle, the host cell is manipulated to replicate the viral DNA alongside its own, ultimately leading to the assembly of new viral particles and the lysis of the host. In the lysogenic cycle, the host cell’s own DNA is replicated normally, and the integrated viral DNA is replicated along with it.
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Viral Protein Synthesis: Viral proteins are synthesized primarily during the lytic cycle when the host cell is actively producing new virus particles. In the lysogenic cycle, viral protein synthesis does not occur until the lysogenic phase is induced into the lytic phase.
In summary, the lytic cycle results in the destruction of the host cell following viral replication and release, while the lysogenic cycle integrates the viral DNA into the host genome, allowing the virus to remain dormant until it triggers a lytic response.