Which cycle is associated with prophage integration into the host chromosome and lysogenic infection?

• A. Lysogenic
• B. Lytic
• C. Pseudolysis
• D. Abortive

Answer: (A)

Lysogenic infection is the process where the phage genome integrates into the host chromosome and exists as a prophage. In this state, the phage DNA is replicated with the bacterial genome during cell division, so the prophage is passed to daughter cells without producing new viral particles. The infection remains dormant until a trigger—often stress or DNA damage—causes the prophage to excise and enter the lytic cycle, leading to phage replication and cell lysis. This differs from the lytic cycle, which immediately produces new phages and ends with host cell breakup, and from pseudolysis or abortive infections, which don't establish a true, productive lysogenic relationship.