Which statement about viruses is true?

Which statement about viruses is true?

• A. They can reproduce without infecting host cells
• B. They cannot reproduce except in host cells
• C. They are larger than bacteria and visible under light microscopy
• D. They have mitochondria

Answer: (B)

Viruses depend on living cells to reproduce. They carry genetic material and a protein coat, but lack the cellular machinery required for copying their genome and making viral proteins. To replicate, a virus must enter a susceptible cell and hijack the host’s ribosomes, enzymes, and energy resources. Outside a host, they do not reproduce; they exist as inert viral particles awaiting infection. Viruses are also much smaller than bacteria and cannot be seen with a light microscope, requiring electron microscopy to visualize them. They have no mitochondria or other cellular organelles, since they are acellular. So the statement that describes their reproduction as occurring only inside host cells is the true one.

Viruses depend on living cells to reproduce. They carry genetic material and a protein coat, but lack the cellular machinery required for copying their genome and making viral proteins. To replicate, a virus must enter a susceptible cell and hijack the host’s ribosomes, enzymes, and energy resources. Outside a host, they do not reproduce; they exist as inert viral particles awaiting infection.

Viruses are also much smaller than bacteria and cannot be seen with a light microscope, requiring electron microscopy to visualize them. They have no mitochondria or other cellular organelles, since they are acellular.

So the statement that describes their reproduction as occurring only inside host cells is the true one.