Transgenic plants of tomato having resistance to hornworm larvae are those which have.

Options

A. Foregin resistance gene
B. Mutuated resistance gene
C. sythetic resistance gene
D. superimposed resistance gene

Answer

To answer the question regarding transgenic plants of tomato that have resistance to hornworm larvae, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Transgenic Plants**: Transgenic plants are genetically modified organisms (GMOs) where genes from other species are inserted into their genomes to give them new traits, such as pest resistance.

2. **Identifying the Target Pest**: In this case, the target pest is the hornworm larvae, which are known to damage tomato plants.

3. **Gene Source for Resistance**: To confer resistance to hornworm larvae, scientists use a specific gene from the bacterium *Bacillus thuringiensis* (Bt). This bacterium produces a protein that is toxic to certain insects, including hornworms.

4. **Mechanism of Action**: When the gene from *Bacillus thuringiensis* is inserted into the tomato plant's genome, the plant can produce the Bt toxin. When hornworm larvae feed on the tomato plant, they ingest the toxin, which disrupts their digestive system and ultimately kills them.

5. **Conclusion**: Therefore, transgenic tomato plants that have resistance to hornworm larvae are those that contain the foreign gene from *Bacillus thuringiensis*.

### Final Answer:
Transgenic plants of tomato having resistance to hornworm larvae are those which have a foreign gene from *Bacillus thuringiensis*.

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