Question

Which molecular technique is used to detect specific mRNA molecules in a sample?

• A. Southern Blot
• B. Northern Blot
• C. Western Blot
• D. PCR

Hint:

Southern blot → DNA
Northern blot → RNA (mRNA detection)
Western blot → Protein

Answer 1

The Correct Option is B

Concept:
Blotting techniques are important molecular biology methods used to detect specific biomolecules such as DNA, RNA, or proteins. Each blotting method is designed to identify a particular type of molecule.
Step 1:Understanding different blotting techniques.
The major blotting techniques include:

• Southern blot – Used to detect specific DNA sequences.
• Northern blot – Used to detect RNA molecules, especially mRNA.
• Western blot – Used to detect specific proteins.

Step 2:Role of Northern blot.
The Northern blot technique separates RNA molecules using gel electrophoresis, transfers them onto a membrane, and detects specific RNA sequences using labeled probes.
Step 3:Application in gene expression analysis.
Northern blot is commonly used to:

• Detect specific mRNA molecules
• Measure gene expression levels
• Study transcription patterns

Conclusion:
Therefore, the molecular technique used to detect specific mRNA molecules in a sample is the Northern blot technique.