Question

____ is a single stranded $DNA$ or $RNA$, tagged with a radioactive molecule and is used to detect mutated genes.

• A. $RNAi$
• B. Probe
• C. Plasmid
• D. Primer

Answer 1

Answer: (B)

A single stranded $DNA$ or $RNA$ joined with a radioactive molecule (probe) is allowed to hybridise to its complementary $DNA$ in a clone of cells. It is followed by detection using autoradiography. The clone having the mutated gene will not appear on the photographic film, because the probe will not have the complementarity with the mutated gene.