Algonquin College Health Program Assessment (AC-HPAT) Practice Exam

In which cycle does a virus cause immediate lysis of the host cell?

1. Lysogenic cycle

2. Lytic cycle

3. Persistent infection

4. Latent phase

The correct answer is: Lytic cycle

The lytic cycle is the process in which a virus infects a host cell and immediately takes over the cell's machinery to replicate itself, ultimately leading to the destruction of the host cell. During this cycle, the viral genetic material hijacks the host cell's resources to produce viral components, which are then assembled into new virus particles. Once sufficient new viruses are formed, the host cell undergoes lysis, or rupture, releasing the newly created viruses into the surrounding environment, ready to infect other cells. This cycle contrasts with the lysogenic cycle, where the viral genome integrates into the host cell's DNA and remains dormant, not causing immediate cell death. Persistent infections involve the gradual release of viruses from the host cell without lysis, allowing the host cell to survive for an extended period, while the latent phase refers to a period of inactivity where the virus is not actively replicating but can reactivate later. Thus, the defining characteristic of the lytic cycle is the rapid and destructive replication of the virus, leading to the immediate lysis of the host cell.