Which of the following physiological activity is not induced by Auxins in plants ?

Options

A. Indole - 3 -butyric acid
B. Napthalene acetic acid
C. 2,3-5 tri chloro phenoxy acetic acid
D. 2,4 dichloro phenoxy acetic acid

Answer

To determine which physiological activity is not induced by auxins in plants, we need to first understand what auxins are and their functions.

### Step-by-Step Solution:

1. **Understand Auxins**: Auxins are a class of plant hormones that play a crucial role in regulating plant growth and development. They are primarily found in the stem apices and other regions of the plant.

2. **Identify Physiological Activities Induced by Auxins**: Auxins are known to induce several physiological activities in plants, including:
- **Elongation of Cells**: Auxins promote the elongation of plant cells, particularly in stems.
- **Apical Dominance**: Auxins help maintain apical dominance, which is the phenomenon where the main central stem of the plant grows more strongly than the other side stems.
- **Root Initiation**: Auxins are involved in the initiation and development of roots.
- **Fruit Development**: Auxins play a role in the development of fruits.

3. **Analyze the Options**: The question asks which physiological activity is not induced by auxins. We need to look at the options provided and identify the one that does not align with the known functions of auxins.

4. **Identify the Correct Answer**: In the context of the question, the option that does not represent a physiological activity induced by auxins is **Indole-3-butyric acid**. While it is related to auxins, it is not a physiological activity itself but rather a type of auxin.

### Final Answer:
The physiological activity that is not induced by auxins in plants is **Indole-3-butyric acid**.

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