Short stretches of DNA used to identify complementary sequence in a sample arecalled

Options

A. probes
B. markers
C. VNTRs
D. primers

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks for the term used to describe short stretches of DNA that can identify complementary sequences in a sample.

2. **Identifying Key Terms:**
- **Short Stretches of DNA:** This indicates we are looking for a specific type of DNA fragment.
- **Identify Complementary Sequences:** This suggests that the DNA fragment has a role in binding to another DNA or RNA sequence that is complementary to it.

3. **Analyzing the Options:**
- **Probes:** Probes are short segments of DNA or RNA that are used to detect the presence of complementary sequences. They can be labeled with radioisotopes or fluorescent tags to visualize binding.
- **Markers:** These are specific locations on DNA that help in identifying certain traits or sequences but do not directly bind to complementary sequences.
- **VNTR (Variable Number of Tandem Repeats):** These are repeating sequences in DNA but are not specifically used for identifying complementary sequences.
- **Primers:** These are short sequences that initiate DNA synthesis during processes like PCR, but they do not serve the purpose of identifying complementary sequences in a sample.

4. **Conclusion:** Based on the analysis, the term that best fits the description of short stretches of DNA used to identify complementary sequences is **Probes**.

5. **Final Answer:** Short stretches of DNA used to identify complementary sequences in a sample are called **Probes**.

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