1. No virus can survive in ocean waters.
2. No virus can infect bacteria.
3. No virus can change the cellular transcriptional activity in host cells.
How many of the statements given above are correct?
Explanation
Statement I is incorrect:
Viruses are the most abundant biological entities in marine ecosystems, with 10 million viruses per milliliter of seawater. Marine viruses, such as cyanophages and bacteriophages, infect phytoplankton, bacteria, and archaea, driving biogeochemical cycles.
Statement II is incorrect:
Bacteriophages (phages) infect only bacteria, not all microbes. Lytic phages (e.g., T4) destroy bacteria like E. coli within 20-30 minutes, while lysogenic phages (e.g., lambda) integrate into host genomes.
Statement III is incorrect:
Viruses manipulate host transcription, e.g., adenoviruses (Ad5) use E1A/E1B proteins to hijack RNA polymerase II, enhancing cyclin E and viral gene expression by 10-100 fold and suppressing IFN-. HIV uses Tat protein to boost transcription by 1000-fold; SARS-CoV-2 suppresses interferon pathways by 80%.
Focus on extreme words like "No virus can...", which signal overgeneralization. All three statements contain the extreme phrase "No virus can...," which overgeneralizes biological facts that are well-documented to the contrary -- making all of them false.