Which of the following describes why a drug may appear effective against a pathogen in clinical susceptibility tests but ineffec
tive in a real-life context? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer. 1. Compared to controlled susceptibility tests, the drug may be less active in a real-life context either due to drug inactivation by body processes or as a result of drug solubility issues.
2. Drug susceptibility tests are typically performed at room temperature (much cooler than human body temperature).
3. In clinical susceptibility tests, drug concentration is well controlled compared to a real-life context.
4. Unlike in controlled clinical susceptibility tests, the number of bacteria varies between tissue samples.
For #1: Outside of a lab, different people's bodies may respond differently to the drug due to a one or many factors such as those listed in the response.
For #4: Pathogen mutations as well as bacterial growth and spread may render the drug incapable of curing the pathogen due to there simply being more bacteria in one person than the drug can handle.
I think the correct answer from the choices listed above is option A. Directional selection can be distinguished from disruptive selection by the elimination of extreme variations of traits. Directional selection is a natural selection where an extreme phenotype is favored than others.
