What are the two life cycles possible for a virus?

What are the two life cycles possible for a virus?

• A. Lytic and Lysogenic
• B. Lysogenic and Lysis
• C. Binary Fission and Lysis
• D. Attachment and Penetration

Answer: (B)

The question tests how a virus can replicate through two distinct strategies: the lytic cycle and the lysogenic cycle. In the lytic cycle, the virus hijacks the host’s machinery to make many copies of itself, then causes the host cell to burst (lysis) to release new virions. In the lysogenic cycle, the viral genome integrates into the host’s DNA and is replicated along with the host genome whenever the cell divides, remaining dormant as a prophage until conditions trigger a switch to the lytic cycle. This is why these two are described as the viral life cycles. Lysis is the outcome of the lytic cycle, not a separate cycle, and other terms like binary fission or attachment and penetration refer to bacterial division or early steps, not complete viral life cycles.

The question tests how a virus can replicate through two distinct strategies: the lytic cycle and the lysogenic cycle. In the lytic cycle, the virus hijacks the host’s machinery to make many copies of itself, then causes the host cell to burst (lysis) to release new virions. In the lysogenic cycle, the viral genome integrates into the host’s DNA and is replicated along with the host genome whenever the cell divides, remaining dormant as a prophage until conditions trigger a switch to the lytic cycle. This is why these two are described as the viral life cycles. Lysis is the outcome of the lytic cycle, not a separate cycle, and other terms like binary fission or attachment and penetration refer to bacterial division or early steps, not complete viral life cycles.