Which of the following best describes a key difference between the lysogenic cycle and the lytic cycle in bacteriophages?

• A. The lysogenic cycle only occurs in Gram-positive bacteria, while the lytic cycle only occurs in Gram-negative bacteria.
• B. During the lysogenic cycle, bacteriophages produce endospores, while in the lytic cycle, they do not.
• C. In the lysogenic cycle, the host cell is rapidly destroyed, whereas in the lytic cycle, the host cell survives indefinitely.
• D. In the lysogenic cycle, viral DNA integrates into the host genome and can remain dormant, while in the lytic cycle, the virus immediately replicates and lyses the host cell.

Answer: (D)

Verified step by step guidance

1. Step 1: Understand the two main bacteriophage life cycles: the lytic cycle and the lysogenic cycle. These are different strategies viruses use to reproduce within bacterial cells.
2. Step 2: In the lytic cycle, the bacteriophage injects its DNA into the host, immediately takes over the host's machinery to produce new viral particles, and eventually causes the host cell to burst (lyse), releasing new viruses.
3. Step 3: In contrast, during the lysogenic cycle, the viral DNA integrates into the host bacterium's genome and remains dormant (prophage state) without causing immediate harm to the host cell.
4. Step 4: The integrated viral DNA can be replicated along with the host genome during cell division, allowing the virus to persist in the bacterial population without killing the host.
5. Step 5: Eventually, environmental triggers can cause the prophage to exit the lysogenic cycle and enter the lytic cycle, leading to active viral replication and host cell lysis.