What is incorrect during amphimixis

Options

A. Swelling of sperm nucleus
B. Initial movement of male nucleus along copulation path
C. Establishment of achromatic spindle by proximal centriole
D. Completion of second meiotic division

Answer

### Step-by-Step Solution:

1. **Understanding Amphimixis**: Amphimixis refers to the process of fertilization where two gametes (sperm and egg) fuse to form a zygote. It is a crucial step in sexual reproduction.

2. **Analyzing the Options**:
- **Option A**: Swelling of sperm nucleus - This is a correct process during amphimixis. The sperm nucleus absorbs water and swells to form the male pronucleus.
- **Option B**: Initial movement of male nucleus along copulation path - This option is incorrect. It is not the male nucleus that moves; rather, it is the sperm nucleus that moves along the copulation path.
- **Option C**: Establishment of achromatic spindle by proximal centriole - This occurs after the fusion of the male and female gametes, making this a correct statement.
- **Option D**: Completion of second meiotic divisions - This is also a correct process as the egg completes its meiotic divisions upon fertilization.

3. **Identifying the Incorrect Statement**: From the analysis, the incorrect statement during amphimixis is **Option B**: Initial movement of male nucleus along copulation path. The correct terminology should refer to the sperm nucleus instead of the male nucleus.

4. **Conclusion**: Therefore, the answer to the question is **Option B**: Initial movement of male nucleus along copulation path.