Certified Professional Food Safety (CP-FS) Practice Exam

Viruses are which of the following compared to bacteria?

1. Larger and more complex

2. Smaller and lack a cell wall

3. Similar in size and structure

4. Dependent on bacteria for reproduction

The correct answer is: Smaller and lack a cell wall

Viruses are indeed smaller than bacteria and lack the complex structure that bacteria have, including a cell wall. This distinction is essential in understanding the fundamental differences between these two types of microorganisms. Bacteria are single-celled organisms with a simple cell structure that includes a cell wall, cell membrane, cytoplasm, and genetic material. They are capable of carrying out all necessary life processes independently, which includes reproduction, metabolism, and response to environmental changes. On the other hand, viruses are much smaller, typically measuring only a fraction of the size of bacteria, and they do not possess a cellular structure; they consist essentially of genetic material (either DNA or RNA) enclosed in a protein coat. They cannot reproduce on their own and must infect a host cell, often including bacteria, to replicate and produce new viral particles. This lack of cellular machinery and structure differentiates viruses from bacteria and is a critical aspect of their biology. Understanding these differences is crucial for food safety practices, as the methods to prevent or control bacterial and viral contamination in food may vary significantly.