What do you mean by respiratory climactic?

Explanation

### Step-by-Step Solution:

1. **Understanding Ethylene**: Ethylene is a plant growth regulator that is in gaseous form. It plays a crucial role in various physiological processes in plants.

2. **Role of Ethylene in Plants**: One of the primary functions of ethylene is to promote senescence (aging) and abscission (the shedding of plant organs like leaves and fruits).

3. **Fruit Ripening**: Ethylene is particularly effective in the process of fruit ripening. It triggers various biochemical changes that lead to the maturation of fruits.

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