Which GA was the first Giberrellin to be discovered?

Options

A. `GA_1`
B. `GA_2`
C. `GA_3`
D. `GA_4`

Answer

**Step-by-Step Solution:**

1. **Understanding Gibberellins**: Gibberellins (GAs) are a class of plant hormones that play a crucial role in regulating various aspects of plant growth and development, such as cell division, elongation, flowering, and fruiting.

2. **Historical Context**: The discovery of gibberellins dates back to 1926 when researchers first identified these hormones. Since then, numerous types of gibberellins have been discovered and classified.

3. **Classification of Gibberellins**: Gibberellins are typically denoted by the prefix "GA" followed by a number (e.g., GA1, GA2, GA3, etc.). This numbering system helps in identifying different types of gibberellins.

4. **Identifying the First Discovered Gibberellin**: Among the various gibberellins identified, GA3 is recognized as the first gibberellin to be discovered. It was not only the first but also the most extensively studied form of gibberellin.

5. **Conclusion**: Based on the historical discovery and classification of gibberellins, the answer to the question "Which GA was the first Gibberellin to be discovered?" is GA3.

**Final Answer**: GA3

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