Question

A nutrition experimenter intends to compare the weight gain of newly weaned male rats fed Diet A with that of rats fed Diet B. To do this, she will feed each diet to 10 rats. She has available 10 rats from one litter and 10 rats from a second litter. Rats in the first litter appear to be slightly healthier.

If the 10 rats from Litter 1 were fed Diet A, what problem would this create for the experiment?
A)Genetics and weight gain would be confounded.
B)Genetics and type of diet would be confounded.
C)Genetics and the gender of the rats would be confounded.
D)The age of the rats and type of diet would be confounded.
E)Type of diet and weight gain would be confounded.

Answer 1

Genetics and diet type would be confounded if all rats from Litter 1 were fed only Diet A, because differences in weight gain could be due to genetic variations rather than the diet, thus biasing the results of the nutrition experiment.

Step-by-step explanation:

If the 10 rats from Litter 1 were only fed Diet A, it would create a problem where genetics and type of diet would be confounded in the experiment. This confounding would occur because any observed differences in weight gain between the two groups of rats could be attributed to either the genetic background of the rats (since they come from different litters) or the diet they are being fed, making it difficult to isolate the effect of the diet on weight gain. A proper experiment design would involve randomly allocating rats from both litters to each diet to ensure that genetic differences are evenly distributed and do not bias the results.