DNA or RNA segment tagged with a radioactive molecule is called

Options

A. Vector
B. Probe
C. Clone
D. Plasmid

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term used to describe a DNA or RNA segment that is tagged with a radioactive molecule.

2. **Analyzing the Options**:
- **Vector**: This refers to a DNA molecule used to carry foreign DNA into another cell. It is not specifically related to radioactive tagging.
- **Probe**: A probe is a single-stranded DNA or RNA fragment that is labeled (which can include radioactive labeling) and is used to detect specific sequences of nucleotides in a sample. This matches the description in the question.
- **Clone**: This term refers to a population of genetically identical individuals, which does not relate to the tagging of DNA or RNA.
- **Plasmid**: This is a small, circular DNA molecule that can replicate independently and is often used as a vector, but it does not specifically refer to a radioactive tag.

3. **Identifying the Correct Answer**: Based on the analysis, the term that fits the description of a DNA or RNA segment tagged with a radioactive molecule is "probe".

4. **Conclusion**: The correct answer to the question is "probe".

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