In the light of the above statements, choose the correct answer
from the options given below:

1. Both Statement I and Statement II are true
2. Both Statement I and Statement II are false
3. Statement I is true but Statement II is false
4. Statement I is false but Statement II is true

   Statement I is true but Statement II is false.

   Northern blotting detects and sizes RNA molecules after gel electrophoresis, while Western blotting identifies and quantifies specific proteins using antibodies—both techniques provide size/molecular weight information and quantification capabilities.​

   In blotting techniques, molecules transfer from gel to membrane primarily by electrotransfer (Western blot uses electric field) or vacuum blotting (modern Northern/Southern); traditional capillary action is rarely used today due to inefficiency.

   Statement I Analysis

   Northern blot separates RNA by size on denaturing agarose gels, transfers to membrane, and hybridizes with labeled probes for detection/quantification of specific transcripts. Western blot uses SDS-PAGE for protein size separation, followed by antibody-based detection for quantity and identity confirmation.​

   Statement II Analysis

   While capillary transfer was originally described for Southern blotting (1975), current protocols favor semi-dry/wet electroblotting (Western) and vacuum/electrotransfer (Northern) for speed and efficiency. Capillary action is outdated and not standard practice.

   Option Breakdown

   Option	Evaluation	Reason
   Both Statement I and Statement II are true	Incorrect	Statement II inaccurately describes modern transfer methods.​
   Both Statement I and Statement II are false	Incorrect	Statement I correctly describes blotting applications.​
   Statement I is true but Statement II is false	Correct	Matches verified applications vs. current transfer techniques.
   Statement I is false but Statement II is true	Incorrect	RNA/protein assignments are accurate; transfer method outdated.​

   Northern Western blotting techniques size RNA and quantify proteins respectively, but use electrotransfer rather than capillary action in modern protocols—essential for NEET/GATE molecular biology.

   Northern Blotting RNA Detection

   Northern blotting separates RNA molecules by size using formaldehyde-agarose gel electrophoresis, transfers via vacuum/electroblotting, then detects specific transcripts with labeled cDNA/RNA probes. Quantifies gene expression levels accurately.​

   Western Blotting Protein Analysis

   Western blotting resolves proteins by molecular weight via SDS-PAGE, transfers by semi-dry electroblotting (15-30 min), then uses primary/secondary antibody detection for specific protein quantification and size confirmation.

   Transfer Method Evolution

   Capillary transfer (original Southern method): gel-membrane-paper stack, 12-24 hours via wicking.
   Modern methods: Electrotransfer (Western: 7-15V/cm), vacuum blotting (Northern: 30-60 min). Capillary action largely obsolete.​

   Exam Application

   Assertion questions test Northern=RNA, Western=protein (Statement I true) vs. transfer mechanism (Statement II false). Option C correct for competitive exams.​