Which one of the following is used as vector for cloning genes into higher organisms

Options

A. Retrovirus
B. Baculovirus
C. Rhizopus nigricans
D. Salmonella typhimurium

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question:**
The question asks which vector is used for cloning genes into higher organisms. A vector is a vehicle used to transfer genetic material into a host cell.

2. **Analyzing the Options:**
The options provided are:
- Retrovirus
- Baculovirus
- Rhizopus nigricans
- Salmonella typhimurium

3. **Evaluating Each Option:**
- **Retrovirus:** Retroviruses can convert their RNA genome into DNA and integrate it into the host's genome. This ability allows for stable gene transfer into mammalian cells, making them suitable for cloning genes into higher organisms, including humans.
- **Baculovirus:** Baculoviruses primarily infect insects and are used for transient protein expression in insect cells. They are not suitable for higher organisms.
- **Rhizopus nigricans:** This is a fungus used as a host vector system for protein synthesis but is not used for cloning genes into higher organisms.
- **Salmonella typhimurium:** This bacterium is a pathogen in humans and is more suitable as a vaccine vector rather than for gene cloning in higher organisms.

4. **Identifying the Correct Answer:**
Based on the analysis, the correct answer is **retrovirus**. Retroviruses are specifically designed to integrate genetic material into the genomes of higher organisms, making them ideal for gene cloning.

5. **Conclusion:**
Therefore, the vector used for cloning genes into higher organisms is **retrovirus**.

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