Sometimes more than 4 pollen grains are produced from one microspore mother cell, it is called

Options

A. Polyembryony
B. Polysiphony
C. Nemec phenomenon
D. Polyspory

Answer

To answer the question about the phenomenon where more than four pollen grains are produced from one microspore mother cell, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Microspore Mother Cell**:
- A microspore mother cell (microsporocyte) undergoes meiosis to produce microspores, which typically develop into pollen grains. Normally, one microspore mother cell produces four pollen grains.

2. **Identifying the Phenomenon**:
- The question specifies a situation where more than four pollen grains are produced from one microspore mother cell. We need to identify the correct term for this occurrence.

3. **Evaluating the Options**:
- **Polyembryony**: This term refers to the formation of multiple embryos from a single fertilized egg, which is unrelated to pollen production. Thus, this option is incorrect.
- **Polysiphony**: This term describes a situation where a single embryo sac is penetrated by multiple pollen tubes. It does not pertain to the production of pollen grains, making this option incorrect as well.
- **Nemec Phenomenon**: This phenomenon is related to the interaction between pollen and the embryo sac but does not specifically address the production of multiple pollen grains. Therefore, this option is also incorrect.
- **Polyspory**: The term "polyspory" combines "poly" (meaning many) with "spory" (related to spores or pollen). This term correctly describes the condition where more than four pollen grains are produced from one microspore mother cell.

4. **Conclusion**:
- Based on the evaluation of the options, the correct answer to the question is **polyspory**.

### Final Answer:
The phenomenon where more than four pollen grains are produced from one microspore mother cell is called **polyspory**.