PCR is used to _____.

• A. Amplify a single gene or small sequence of DNA.
• B. Create DNA without introns.
• C. Insert foreign DNA into a host cell where it can be replicated.
• D. Cut segments of DNA creating complimentary sticky ends.
• E. None of these.

Answer: (A)

Verified step by step guidance

1. Understand the purpose of PCR (Polymerase Chain Reaction): PCR is a technique used in molecular biology to amplify a specific segment of DNA, making millions of copies of a particular DNA sequence.
2. Identify the correct function of PCR from the given options: PCR is primarily used to amplify a single gene or small sequence of DNA, which is essential for various applications such as cloning, sequencing, and analysis.
3. Clarify why other options are incorrect: Creating DNA without introns is typically done through cDNA synthesis, inserting foreign DNA into a host cell is related to genetic engineering techniques like transformation, and cutting DNA to create sticky ends is done by restriction enzymes.
4. Recognize the importance of PCR in research and diagnostics: PCR is crucial for detecting and analyzing genetic material, allowing scientists to study genes and diagnose diseases.
5. Conclude with the correct application of PCR: Amplifying a single gene or small sequence of DNA is the primary function of PCR, making it a powerful tool in molecular biology.