Question

The efficiency of PCR amplification in DNA barcoding can be enhanced by the presence of which mineral nutrient known for its stabilizing effect on DNA polymerase?

• A. Rhodium
• B. Ruthenium
• C. Osmium
• D. Iridium

Hint:

Think about which of these four metals is actually studied in connection with DNA, even though none of them is the standard PCR cofactor.

Answer 1

The Correct Option is B

Step 1: Understanding the Question.
The question asks which metal, among four transition or noble metals, is said to help PCR work better by stabilizing DNA polymerase.

Step 2: Key Background.
In real PCR chemistry, the enzyme, usually Taq polymerase, needs Mg2+ as its main cofactor, with Mn2+ sometimes used as a substitute. None of Rhodium, Ruthenium, Osmium or Iridium is the textbook cofactor of DNA polymerase, so this question sits outside the usual syllabus fact.

Step 3: Detailed Explanation.
Among the four choices, Ruthenium is the one most studied in connection with DNA. Ruthenium complexes are well known for binding to and intercalating the DNA double helix, and they are used in electrochemical DNA sensors and DNA damage studies, work that involves DNA-handling enzymes such as polymerases. Rhodium, Osmium and Iridium are mainly used in catalysis, electrical contacts or as a heavy-metal stain (osmium tetroxide) for electron microscopy, with no reported role in stabilizing DNA polymerase.

Step 4: Final Answer.
Ruthenium is picked as the best-supported answer here because it has the closest documented link to DNA chemistry among the four options, though this is not a mainstream, well-established fact the way Mg2+ is for DNA polymerase, so some uncertainty remains. \[ \boxed{\text{Ruthenium}} \]