Ethylene promotes (A)____ and (B)____ of plant organs especially of leaves and flowers.

Answer

To answer the question regarding the effects of ethylene on plant organs, particularly leaves and flowers, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Ethylene**: Recognize that ethylene is a gaseous plant hormone that plays a significant role in various physiological processes in plants.

2. **Functions of Ethylene**: Identify the key functions of ethylene. It is known to promote several processes, including:
- Horizontal growth of seedlings
- Swelling of plant axes
- Apical hook formation in dicot seedlings

3. **Focus on Senescence and Abscission**: Specifically, ethylene is known to promote:
- **Senescence**: This refers to the aging process in plants, leading to the eventual death of plant organs, particularly leaves and flowers.
- **Abscission**: This is the process of shedding or dropping off of leaves, flowers, or fruits, which is often associated with the aging of these organs.

4. **Filling in the Blanks**: Based on the understanding of ethylene's functions, we can fill in the blanks in the question:
- (A) Senescence
- (B) Abscission

### Final Answer:
Ethylene promotes (A) **senescence** and (B) **abscission** of plant organs, especially of leaves and flowers.

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