Question

If you are testing types of poisons on rats to determine which one is the most deadly, which of the following would represent a variable that must be constant or controlled to ensure a good experiment?

a) Rat species
b) Poison type
c) Rat size
d) Room temperature

Answer 1

In a toxicity study on rats, room temperature must be controlled to ensure reliable results, as variations can impact the metabolism and effects of the poisons on the rats, leading to inaccurate data.

Step-by-step explanation:

In a scientific experiment testing the toxicity of different poisons on rats, the variable that must be kept constant to ensure a valid experiment is d) Room temperature. Factors such as rat species, poison type, and rat size are variables that define the conditions of the experiment and are integral to what is being tested or observed. However, to ensure that the results are due to the toxicity of the poisons and not other external factors, environmental conditions like room temperature must be controlled.

Consistent environmental conditions eliminate confounding variables that could otherwise affect the rats' metabolism and response to the poisons. For example, if the room temperature varies greatly, it could influence how quickly a poison acts or is metabolized by the rats, which could lead to inaccurate results. Therefore, in toxicity studies, it is crucial to control such environmental variables to obtain reliable and replicable data about the lethality of the poisons being tested.