Which statement best describes how a virus differs from a bacterium?

• A. A virus is a type of prokaryotic cell that contains ribosomes and divides by mitosis, whereas a bacterium lacks ribosomes and cannot reproduce on its own.
• B. A virus is acellular and must use a host cell’s machinery to replicate, whereas a bacterium is a cellular organism that can reproduce independently by binary fission.
• C. A virus is always larger than a bacterium and can grow on nutrient agar without a host, whereas a bacterium requires living cells to replicate.
• D. A virus has both DNA and RNA and generates ATP independently, whereas a bacterium has only DNA and must rely on a host cell for energy production.

Answer: (B)

Verified step by step guidance

1. Understand the fundamental nature of viruses and bacteria: Viruses are acellular entities, meaning they are not made up of cells, while bacteria are unicellular organisms classified as prokaryotes.
2. Recognize that viruses lack the cellular machinery necessary for independent metabolism and reproduction; they must infect a host cell and hijack its machinery to replicate.
3. Recall that bacteria have cellular structures such as ribosomes, can carry out metabolic processes independently, and reproduce by binary fission without needing a host.
4. Evaluate each statement by comparing these key differences: whether the entity is cellular or acellular, its ability to reproduce independently, and its metabolic capabilities.
5. Identify the statement that correctly reflects these distinctions: that viruses are acellular and require host machinery for replication, whereas bacteria are cellular organisms capable of independent reproduction.