Would ID50 and LD50 Necessarily Be the Same for a Given

question 54

Multiple Choice

Would ID50 and LD50 necessarily be the same for a given virus? Why or why not?

• A) Yes, because the number of viruses that infect 50% of a test population should also kill 50% of that test population.
• B) No, because a virus may be highly infectious (very low ID50 value) but only marginally lethal (very high LD50 value), for example the rhinovirus (common cold virus).
• C) No, because very few viruses are lethal, yet many are highly infectious. The two values should ALWAYS be different.
• D) Yes, because what we're actually describing here is the infection/ killing of individual cells, not of entire organisms. If a cell is infected, it will always be killed.
• E) Yes, because ID50 and LD50 are actually measurements of the same thing: effectiveness of a virus in entering and damaging a host cell.

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Definitions:

Random Allocation

A method used in experiments where participants are assigned to different groups in a way that ensures each participant has an equal chance of being placed in any group.

Experimenter Bias

A phenomenon where the expectations or beliefs of the researcher unconsciously affect the outcome of an experiment.

Socially Desirable

Describes behaviors or responses that are likely to be approved of or valued by society or a social group.

Experimental Manipulation

The process of intentionally changing variables to observe the effect on another variable within a controlled environment.