A sterile stamen is known as

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Stamen**: The stamen is the male reproductive organ of a flower. It consists of two main parts: the anther and the filament. The anther produces pollen, which contains male gametes.

2. **Defining Sterile Stamen**: A sterile stamen is one that does not produce pollen. This means it is not capable of fertilizing an ovule and is therefore considered non-functional in terms of reproduction.

3. **Characteristics of Sterile Stamens**: Sterile stamens can be described as rudimentary or abortive. This indicates that they may be underdeveloped or completely non-functional.

4. **Occurrence of Sterile Stamens**: Sterile stamens are often found in certain plant families, such as the orchid family (Orchidaceae) and in species like Penstemon.

5. **Terminology**: The term used to refer to a sterile stamen is "staminode." This term specifically denotes a stamen that does not produce pollen.

6. **Conclusion**: Therefore, a sterile stamen is known as a staminode.

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