A researcher introduces double-stranded RNA into a culture of mammalian cells, and can identify its location or that of its smaller subsections experimentally, using a fluorescent probe.
-Within the first quarter hour, the researcher sees that the intact RNA is found in the cells. After 3 hours, she is not surprised to find that

Question

Quizplus · Accepted Answer

After being introduced into mammalian cells, double-stranded RNA is recognized by the Dicer enzyme, which cleaves it into smaller double-stranded pieces known as siRNAs. This process occurs within the first quarter hour of introduction. Therefore, after 3 hours, it is expected that the RNA will have been reduced to smaller pieces by Dicer. Option B is incorrect because exonucleases degrade single-stranded RNA, not double-stranded RNA. Option C is incorrect because double-stranded RNA does not replicate itself in mammalian cells. Option D and E are incorrect because double-stranded RNA binds to mRNAs to trigger RNA interference and prevent translation, not bind to tRNAs.

A Researcher Introduces Double-Stranded RNA into a Culture of Mammalian