Lysogenic cycle

Definition

The lysogenic cycle is a phase in the life cycle of certain viruses where the viral genome integrates into the host cell's DNA and replicates along with it without causing immediate lysis. This integration allows the virus to persist in a dormant state within the host cell until triggered to enter the lytic cycle.

5 Must Know Facts For Your Next Test

1. The lysogenic cycle involves the incorporation of the viral DNA into the host cell's chromosome, forming a prophage.
2. A virus in the lysogenic cycle can remain dormant for long periods before becoming active.
3. Environmental triggers or stressors can cause a prophage to exit the lysogenic cycle and enter the lytic cycle, leading to active viral replication and cell lysis.
4. Lysogeny can benefit viruses by allowing them to spread without killing their host cells immediately, which aids in long-term survival.
5. Bacteriophages are well-studied examples of viruses that undergo both lysogenic and lytic cycles.

Review Questions

• What triggers a prophage to switch from the lysogenic cycle to the lytic cycle?
• How does integration into host DNA benefit viruses during the lysogenic cycle?
• What is formed when viral DNA integrates into a bacterial chromosome?

Related terms

Lytic Cycle: A phase in which a virus replicates inside a host cell leading to its destruction.

Prophage: Viral DNA that has integrated into a bacterial genome during the lysogenic cycle.

Bacteriophage: A type of virus that infects bacteria, capable of undergoing both lysogenic and lytic cycles.