Which one produces more ethylene?

Options

A. Unripe apple
B. Unripe banana
C. Ripening banana
D. Mature banana leaf

Answer

To determine which option produces more ethylene, let's analyze the information provided step by step.

### Step-by-Step Solution:

1. **Understanding Ethylene**: Ethylene is a plant hormone that exists as a gas (C2H4) and plays a crucial role in regulating plant growth, development, and the ripening of fruits.

2. **Role of Ethylene in Ripening**: Ethylene is known to facilitate the ripening process in fruits. When a ripe fruit is present, it releases ethylene gas, which can trigger the ripening of nearby unripe fruits.

3. **Identifying the Options**: The question presents four options:
- Unripe apple
- Unripe banana
- Mature banana leaf
- Ripening banana

4. **Analyzing Each Option**:
- **Unripe Apple**: While apples do produce ethylene, they are not as prolific in ethylene production as some other fruits.
- **Unripe Banana**: Unripe bananas do not produce significant amounts of ethylene until they start to ripen.
- **Mature Banana Leaf**: Leaves generally do not produce ethylene in significant amounts compared to fruits.
- **Ripening Banana**: A ripening banana is actively producing ethylene, which aids in its own ripening and can also influence nearby fruits.

5. **Conclusion**: Among the options provided, the ripening banana produces the most ethylene. Therefore, the correct answer is the **ripening banana**.

### Final Answer:
The option that produces more ethylene is the **ripening banana**.

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