Question

The question consist of two statements – Assertion (A) and Reason (R). Answer these questions selecting the appropriate option given below:

• A. Both (A) and (R) are true and (R) is the correct explanation of (A).
• B. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
• C. (A) is true, but (R) is false.
• D. (A) is false, but (R) is true.
  Assertion (A): In molecular diagnosis, single-stranded DNA or RNA tagged with a radioactive molecule is called a probe.
  Reason (R): A probe always searches and hybridises with its complementary DNA in a clone of cells.

Hint:

Probes are crucial in techniques like Southern blotting and in situ hybridisation for detecting specific DNA or RNA sequences.

Answer 1

The Correct Option is A

Probes are single-stranded DNA or RNA molecules tagged with a radioactive or fluorescent label. They hybridise with complementary sequences in target DNA during molecular diagnosis, making them highly specific for detecting genetic abnormalities.