Transgenic Brassica napus has been used for the synthesis of:

Options

A. Hirudin
B. Herparin
C. Polgalacturonase
D. Cry protein

Answer

To answer the question regarding what transgenic Brassica napus has been used for the synthesis of, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Transgenic Organisms**:
- Transgenic organisms are those that have had a foreign gene deliberately inserted into their genome. This process alters their genetic material.

2. **Identifying the Options**:
- The options provided are:
- Herodin
- Herparin
- Polygalacturonase
- Cryoprotein

3. **Researching the Function of Each Option**:
- **Herodin**: A protein that prevents blood clotting.
- **Herparin**: An anticoagulant used to prevent blood clots.
- **Polygalacturonase**: An enzyme involved in the breakdown of pectin in plant cell walls.
- **Cryoprotein**: Proteins that protect cells from freezing.

4. **Determining the Correct Answer**:
- The gene encoding **herodin** was chemically synthesized and then transferred into Brassica napus. This allows the plant to produce herodin, which accumulates in its seeds and can be purified for medicinal use.

5. **Conclusion**:
- Based on the above analysis, the correct answer is that transgenic Brassica napus has been used for the synthesis of **herodin**.

### Final Answer:
Transgenic Brassica napus has been used for the synthesis of **herodin**.

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