MHT CET Medical202623 April 2026Evening ShiftBiologyMolecular Basis of InheritanceActual
Given below are two statements about DNA fingerprinting. Statement (I): The DNA probe used in DNA fingerprinting is a dsDNA obtained from organisms only. Statement (II): The DNA probe is labeled with radioisotopes and added to nitrocellulose filter paper. In light of the above statements, choose the most appropriate answer from the options given below.
Options
- ABoth Statement (I) and Statement (II) are correct.
- BBoth Statement (I) and Statement (II) are incorrect.
- CStatement (I) is incorrect but Statement (II) is correct.
- DStatement (I) is correct but Statement (II) is incorrect.
Correct answer
C. Statement (I) is incorrect but Statement (II) is correct.
Step-by-step solution
Statement (I) is incorrect because the DNA probe used in DNA fingerprinting is a single-stranded DNA (ssDNA) or single-stranded RNA (ssRNA), not double-stranded DNA (dsDNA). Furthermore, probes can be artificially synthesized in the laboratory and are not exclusively obtained from organisms. Statement (II) is correct because during the Southern blotting step of DNA fingerprinting, the single-stranded DNA fragments are transferred to a synthetic membrane such as nitrocellulose or nylon. A radiolabelled single-strand