Select the correct statement from the following with regard to procedures of the biotechnology

Options

A. Gel electrophoresis is used for amplification of a DNA segment.
B. The polymerase enzyme joins the gene of interest and the vector DNA.
C. Restriction enzyme digestions are performed by incubating purified DNA molecules with the restriction enzymes of optimum conditions.
D. PCR is used for isolation and separation of gene of interest.

Answer

To solve the question regarding the correct statement about the procedures of biotechnology, we will analyze each of the provided statements step by step.

### Step-by-Step Solution:

1. **Statement 1: Gel electrophoresis is used for the amplification of the DNA segment.**
- **Analysis:** Gel electrophoresis is a technique used to separate DNA fragments based on size and charge. It does not amplify DNA; rather, it is used after DNA has been cut into fragments by restriction enzymes. Therefore, this statement is **incorrect**.

2. **Statement 2: Polymerase enzyme joins the genes of interest and the vector DNA.**
- **Analysis:** The polymerase enzyme is primarily involved in synthesizing DNA strands during replication or amplification processes, such as PCR. The joining of DNA segments is performed by DNA ligase, not polymerase. Hence, this statement is also **incorrect**.

3. **Statement 3: Restriction enzyme digestions are performed by incubating purified DNA molecules with the restriction enzymes at the optimum conditions.**
- **Analysis:** This statement accurately describes the process of using restriction enzymes to cut DNA. Purified DNA is indeed incubated with restriction enzymes under optimal conditions to achieve digestion. Therefore, this statement is **correct**.

4. **Statement 4: PCR is used for isolation and separation of the gene of interest.**
- **Analysis:** Polymerase Chain Reaction (PCR) is a method used to amplify DNA, creating multiple copies of a specific DNA segment. It is not used for isolation or separation; those processes are typically done using techniques like gel electrophoresis. Thus, this statement is **incorrect**.

### Conclusion:
The correct statement regarding the procedures of biotechnology is **Statement 3**: "Restriction enzyme digestions are performed by incubating purified DNA molecules with the restriction enzymes at the optimum conditions."

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