Question 1

Which blotting technique is primarily used for the detection of specific RNA sequences in a sample?

Accepted Answer

Northern blot

Question 2

A researcher wants to identify the presence of a specific protein in a tissue sample. Which blotting technique should they use?

Accepted Answer

Western blot

Question 3

Which of the following is a major limitation of blotting techniques?

Accepted Answer

They are time- and labor-intensive and have low sensitivity compared to newer methods.

Question 4

During the blotting process, what is the primary purpose of transferring molecules from a gel to a membrane?

Accepted Answer

To allow for specific detection using labeled probes or antibodies

Question 5

Which step comes first in the standard blotting workflow?

Accepted Answer

Gel electrophoresis

Question 6

A scientist is studying gene expression by detecting mRNA levels in cells. Which blotting technique should they use?

Accepted Answer

Northern blot

Question 7

Which of the following equations best represents the relationship between migration distance ($d$) and molecular size ($M$) in gel electrophoresis?

Accepted Answer

$d \propto \frac{1}{M}$

Question 8

Why is it important to use a labeled probe in blotting techniques?

Accepted Answer

To visualize and specifically detect the target molecule on the membrane

Question 9

Which alternative technique to blotting is mentioned as being more sensitive and quantitative for DNA and RNA analysis?

Accepted Answer

PCR (Polymerase Chain Reaction)

Question 10

A patient’s blood sample is analyzed for the presence of a specific viral protein. Which technique is most appropriate?

Accepted Answer

Western blot

Question 11

Which of the following is NOT a target molecule for any of the classic blotting techniques?

Accepted Answer

Lipid

Question 12

In a Western blot, what is the role of the primary antibody?

Accepted Answer

To bind specifically to the target protein

Question 13

Which blotting technique is most commonly used to confirm the presence of a specific DNA sequence?

Accepted Answer

Southern blot

Question 14

A researcher is comparing the expression levels of a protein in healthy and diseased tissue samples. Which technique should they use for quantitative analysis?

Accepted Answer

Western blot

Question 15

Which of the following steps is essential for ensuring specificity in blotting techniques?

Accepted Answer

Using a labeled probe or antibody that binds only to the target molecule

Question 16

Which of the following is a common misconception about Western blotting?

Accepted Answer

It can detect RNA molecules.

Question 17

A sample is run on a gel, transferred to a membrane, and then probed with a labeled DNA fragment. What is being detected?

Accepted Answer

DNA

Question 18

Which of the following best describes the main advantage of PCR over blotting techniques for nucleic acid detection?

Accepted Answer

PCR allows for rapid, quantitative, and highly sensitive detection.

Question 19

In the context of clinical diagnostics, why might Western blotting be used to confirm a positive result from an initial screening test?

Accepted Answer

It provides higher specificity for the target protein.

Question 20

Which of the following correctly lists the steps of a standard blotting technique in order?

Accepted Answer

Gel electrophoresis, transfer to membrane, probe hybridization, detection

Blotting Techniques: North, South, and East Blots in Molecular Biology

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