Bunuel wrote:
Many researchers believe that the presence of RNA in brain cells is the biochemical basis of memory; that is, the presence of RNA enables us to remember. Because certain chemicals are known to inhibit the synthesis of RNA in the body, we can test this hypothesis. Animals that have learned particular responses can be injected with an RNA inhibitor and then tested for memory of the learned responses.
Which of the following test results would most seriously weaken the case for the presence of RNA as the basis of memory?
A. After an injection of RNA inhibitor, a wide range of behaviors in addition to the learned responses were affected.
B. After an injection of RNA inhibitor, animals that had not consistently been giving the learned responses were able to give them consistently.
C. After injections of RNA inhibitor, some animals lost memory of the learned responses totally but others lost it only partially.
D. After a small injection of RNA inhibitor, animals responded well, but as the size of the injection increased, they gave fewer of the learned responses.
E. After an injection of RNA inhibitor, animals could not learn a new response.
OFFICIAL EXPLANATION
The researchers believe that the presence of RNA enables us to remember. However, if, after an injection of RNA inhibitor, animals gave learned responses more consistently than before, it would appear that the absence of RNA facilitates memory.
Therefore, the correct answer is B.A is incorrect. These results would suggest that RNA is the basis of other abilities in addition to that of memory, but there is nothing in them that would weaken the case for RNA as the basis of memory. C is not correct. These results support the case that RNA is the basis of memory, although they suggest that the degree of effectiveness of either RNA or RNA inhibitor may vary. D is incorrect. These results would suggest that RNA must be strongly inhibited in order to impair memory, but still support the case for RNA as the basis of memory. The last answer choice is also incorrect. These results would suggest that RNA is necessary for new learning, and as the learning would require memory, the results would support the case for RNA as the basis of memory.