Which of following sequence followed in human embryology is correct ?

Options

A. Syngamy `to` II meiotic division completed `to` Plasmogamy `to` Karyogamy
B. II–meiotic division completed `to` syngamy `to` plasmogamy `to` karyogamy
C. Syngamy `to` Plasmogamy `to` II meiotic division completed `to` Karyogamy
D. Syngamy `to` plasmogamy `to` karyogamy `to` II meiotic division completed

Answer

To determine the correct sequence followed in human embryology, we need to understand the processes involved in fertilization and early embryonic development. Here’s a step-by-step breakdown of the correct sequence:

### Step-by-Step Solution:

1. **Sygamy**: This is the initial step where two gametes (sperm and egg) fuse to form a zygote. This process marks the beginning of fertilization.

2. **Second Meiotic Division Completed**: After fertilization, the zygote undergoes the second meiotic division. This division results in the formation of haploid cells, which are essential for the development of the embryo.

3. **Plasmogamy**: This term refers to the fusion of the cytoplasm of two cells. In the context of fertilization, it describes the merging of the cytoplasmic contents of the sperm and egg cells.

4. **Karyogamy**: This is the final step where the nuclei of the sperm and egg fuse together. This results in the formation of a diploid nucleus, which is crucial for the development of the embryo.

### Conclusion:
The correct sequence in human embryology is:
- Sygamy → Second Meiotic Division Completed → Plasmogamy → Karyogamy