Which of the following tools of recombinant DNA technology is incorrectly paired with its use

Options

A. restriction enzyme-Production of RFLPs
B. DNA ligase-that outs DNA, creating the sticky ends
C. DNA polymerase - used in a polymerase chain reaction to amplify section of DNA
D. reverse transcriptase - production of cDNA from mRNA

Answer

To solve the question of which tool of recombinant DNA technology is incorrectly paired with its use, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Option A: Restriction Enzyme - Production of RFLP**
- Restriction enzymes are proteins that cut DNA at specific sequences. The fragments produced can be analyzed for variations in DNA sequences, known as Restriction Fragment Length Polymorphisms (RFLP).
- **Conclusion**: This pairing is correct.

2. **Option B: DNA Ligase - Cuts out DNA creating the sticky end**
- DNA ligase is an enzyme that joins two DNA fragments together by forming a phosphodiester bond. It does not cut DNA; instead, it is responsible for sealing nicks in the DNA backbone. The cutting of DNA to create sticky ends is done by restriction enzymes, not DNA ligase.
- **Conclusion**: This pairing is incorrect.

3. **Option C: DNA Polymerase - Used in a polymerase chain reaction to amplify sections of DNA**
- DNA polymerase is indeed used in the polymerase chain reaction (PCR) to amplify specific segments of DNA. It synthesizes new DNA strands complementary to the template strand.
- **Conclusion**: This pairing is correct.

4. **Option D: Reverse Transcriptase - Production of cDNA from mRNA**
- Reverse transcriptase is an enzyme that synthesizes complementary DNA (cDNA) from an RNA template, such as mRNA. This process is known as reverse transcription.
- **Conclusion**: This pairing is correct.

### Final Answer:
The incorrectly paired tool of recombinant DNA technology is **Option B: DNA ligase that cuts out DNA creating the sticky end**.

---