Ori sequence in plasmid refers to sequence

Options

A. for antibody resistance
B. from which replication will start In plasmid
C. for restriction site
D. Both (a) and (b)

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question is asking about the Ori sequence in a plasmid and what it refers to.

2. **Define Ori Sequence**: The Ori sequence, short for "origin of replication," is a specific sequence of nucleotides in a plasmid where DNA replication begins.

3. **Function of Ori Sequence**: The Ori sequence is crucial because it allows the plasmid to replicate independently within a host cell. This is essential for the plasmid to be maintained and passed on during cell division.

4. **Evaluate the Options**:
- **Option A**: Refers to antibiotic resistance. This is incorrect as the Ori sequence does not relate to antibiotic resistance.
- **Option B**: Refers to the point where replication starts in the plasmid. This is correct, as the Ori sequence is indeed where replication begins.
- **Option C**: Refers to a restriction site. This is incorrect; restriction sites are different sequences used for cutting DNA.
- **Option D**: States both A and B. This is incorrect since only option B is correct.

5. **Conclusion**: The correct answer is option B, which states that the Ori sequence in a plasmid refers to the point where replication will start.

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