Name: The key ingredient found in Neem.

Answer

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

1. **Identify the Plant**: The question asks for the key ingredient found in neem. Neem is a well-known medicinal plant.

2. **Recognize the Key Ingredient**: The key ingredient in neem that contributes to its medicinal properties is called azadiractin.

3. **Understand Azadiractin**: Azadiractin is a naturally occurring compound that belongs to a specific class of organic molecules known as tetranortretarpinoins.

4. **Relate to Insect Hormones**: Azadiractin is structurally similar to certain insect hormones, particularly ecdysteroids, which are involved in the growth and development of insects.

5. **Applications of Azadiractin**: Due to its properties, azadiractin is used as a fungicide and insecticide, making neem effective in pest control and providing various medicinal benefits.

6. **Conclusion**: The key ingredient found in neem is azadiractin, which is responsible for its important medicinal and pesticidal properties.

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