In lysogeny a virus is

Options

A. temperate but is capable of virulence
B. virulent
C. completely harmless to host
D. multiplies rapidly

Answer

**Step-by-Step Solution:**

1. **Understanding Lysogeny**:
- Lysogeny is a type of viral reproductive cycle, which is one of two main cycles (the other being the lytic cycle). In this cycle, the virus integrates its genetic material into the host bacterium's genome.

2. **Integration of Viral Nucleic Acid**:
- During lysogeny, the nucleic acid of the bacteriophage (the virus that infects bacteria) becomes integrated into the bacterial genome. This means that the viral DNA is incorporated into the DNA of the host bacterium.

3. **Characteristics of the Virus in Lysogeny**:
- In this state, the virus is not actively replicating or causing harm to the host. Instead, it remains dormant within the host's genome. However, it retains the potential to become virulent (capable of causing disease) under certain conditions.

4. **Analyzing the Options**:
- **Option A**: Tampered but capable of virulence – This aligns with the definition of lysogeny, as the virus is integrated but can still become active.
- **Option B**: Virulent – This does not apply since the virus is not actively causing disease during lysogeny.
- **Option C**: Completely harmless to the host – While it may seem harmless, the virus is still capable of becoming virulent.
- **Option D**: Multiplied rapidly – This describes the lytic cycle, not lysogeny.

5. **Conclusion**:
- Based on the characteristics of lysogeny and the analysis of the options, the correct answer is **Option A**: Tampered but capable of virulence.

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