Which one of the following hormones is not found in plants?

Options

A. 2,4 -D
B. `GA_(2)`
C. Zeatin
D. IAA

Answer

To determine which hormone is not found in plants, we will analyze the options provided:

1. **2,4-D**: This is a synthetic auxin, commonly used as a herbicide to control weeds. While it mimics the action of natural plant hormones, it is not produced by plants themselves.

2. **Gibberellin (GA2)**: This is a natural plant hormone that promotes growth and development in plants. It is involved in processes such as seed germination and stem elongation.

3. **IAA (Indole-3-acetic acid)**: This is another natural plant hormone classified as an auxin. It plays a crucial role in plant growth and development, influencing cell elongation, root formation, and other growth processes.

4. **Zeatin**: This is a type of cytokinin, a natural plant hormone that promotes cell division and growth, particularly in the shoot tips of plants.

From the analysis, we can conclude that:

- **2,4-D** is the only option that is not naturally found in plants, as it is a synthetic compound used for agricultural purposes.

**Final Answer**: 2,4-D is the hormone that is not found in plants.