Question

Which of the following statements concerning Koch's postulates is false? ______

A) Koch's postulates cannot be used to demonstrate the cause of all diseases.
B) Koch's postulates involve the experimental infection of susceptible hosts.
C) All of Koch's postulates must be satisfied before an organism can be shown to cause a particular disease.
D) A suspected pathogen must be able to be grown in the laboratory.
E) The suspected pathogen may not be present in all cases of the disease being studied.

Answer 1

The false statement is E) The suspected pathogen may not be present in all cases of the disease being studied because Koch's postulates assume the organism must always be present in diseased individuals and not in healthy ones, which has been proven not always true.

Step-by-step explanation:

The statement concerning Koch's postulates that is false is E) The suspected pathogen may not be present in all cases of the disease being studied. Koch's postulates were developed by Robert Koch to establish a causal relationship between a microbe and a disease. Koch originally stated that the organism must always be present in individuals suffering from the disease and not present in healthy individuals. However, subsequent findings, such as carriers of pathogens who remain asymptomatic, have challenged this assertion. Moreover, some microorganisms like certain viruses and prions cannot be grown in pure culture, which is required by the second postulate. It is also now known that some pathogens, such as H. pylori, can exist in healthy individuals as part of the normal microbiota without causing disease.

'The false statement is E) The suspected pathogen may not be present in all cases of the disease being studied.'