Question

Differentiate between the lysogenic and lytic cycles.
Responses

The host cell copies its own DNA during the lytic cycle.
The host cell copies its own DNA during the lytic cycle. - no response given

The virus injects DNA into the host cell during the lysogenic cycle.
The virus injects DNA into the host cell during the lysogenic cycle. - no response given

The host cell is destroyed during the lytic cycle.
The host cell is destroyed during the lytic cycle. - no response given

Viral proteins are synthesized during the lysogenic cycle.

Answer 1

Here’s a quick evaluation of each statement and a short clear contrast between the two cycles.

Statement evaluations
- "The host cell copies its own DNA during the lytic cycle." — False. In the lytic cycle the virus hijacks the host machinery to replicate viral genomes (and often degrades or suppresses host DNA replication).
- "The virus injects DNA into the host cell during the lysogenic cycle." — Misleading/false as written. Injection of viral nucleic acid into the host occurs at infection; after injection the virus may enter either the lysogenic or the lytic pathway. Injection is not unique to the lysogenic cycle.
- "The host cell is destroyed during the lytic cycle." — True. New virions are assembled and the cell is lysed (destroyed) to release them.
- "Viral proteins are synthesized during the lysogenic cycle." — Generally false. In lysogeny viral genes are mostly silent while the prophage genome is replicated passively with the host; only a few regulatory proteins (e.g., repressor proteins) are usually produced. Full viral protein synthesis occurs when the prophage is induced into the lytic cycle.

Key differences (brief)
- Lytic cycle: viral genome replicated actively, many viral proteins made, new virions assembled, host cell lysed and destroyed.
- Lysogenic cycle: viral genome integrates (or persists) in host genome as a prophage, is replicated with host cell division, viral genes largely dormant until induction triggers the lytic cycle.