Which of the following best describes the role of Koch's postulates in microbiology?

• A. They explain the structure of bacterial cell walls.
• B. They provide criteria to establish a causal relationship between a microbe and a disease.
• C. They outline the steps for Gram staining bacteria.
• D. They describe the process of viral replication.

Answer: (B)

Verified step by step guidance

1. Understand that Koch's postulates are a set of criteria developed to link a specific microorganism to a particular disease.
2. Recognize that these postulates help establish a causal relationship by demonstrating that the microorganism is found in all cases of the disease, can be isolated and grown in pure culture, causes the disease when introduced into a healthy host, and can be re-isolated from the experimentally infected host.
3. Note that Koch's postulates do not describe bacterial cell wall structure, which is a topic related to bacterial morphology and biochemistry.
4. Acknowledge that Gram staining is a laboratory technique used to differentiate bacteria based on cell wall properties, but it is unrelated to Koch's postulates.
5. Understand that viral replication involves processes specific to viruses and is not covered by Koch's postulates, which focus on microbial causation of disease.