STANDARD Zoology Probes MCQ Question

Single stranded RNA (ssRNA) tagged with a radioactive molecule is used as a probe because it can hybridize specifically to complementary nucleic acid sequences, allowing for the detection of RNA targets in various assays. This specificity is crucial for applications such as Northern blotting and in situ hybridization.

In contrast, single stranded DNA (ssDNA) (Option A) can also be used as a probe, but it is less common for RNA detection. Double stranded DNA (dsDNA) tagged with a radioactive molecule (Option B) is primarily used for DNA detection rather than RNA, and double stranded RNA (dsRNA) (Option D) is typically not used as a probe due to its stability and inability to hybridize effectively with single stranded targets.