The term fertilisation is related to

Options

A. Fusion of two cells
B. Fusion of two nuclei
C. Fusion of two gametes
D. Fusion of two gametic nuclei.

Answer

**Step-by-Step Solution:**

1. **Understanding Fertilization**: The term "fertilization" refers to the process in sexual reproduction where male and female gametes (sperm and egg) fuse together. This fusion is essential for the formation of a new organism.

2. **Identifying the Processes**: In sexual reproduction, there are three main processes:
- **Pre-fertilization**: This includes processes that occur before fertilization, such as gametogenesis (the formation of gametes) and gamete transfer (the movement of gametes to the site of fertilization).
- **Fertilization**: This is the actual fusion of male and female gametes.
- **Post-fertilization**: This involves the changes and developments that occur after fertilization, leading to the formation of an embryo.

3. **Fertilization Process**: During fertilization, the male gamete (sperm) and the female gamete (egg) combine to form a zygote. The zygote is the first cell of a new organism and will undergo further development into an embryo.

4. **Conclusion**: Based on the understanding of the processes involved in sexual reproduction, we can conclude that the term "fertilization" is specifically related to the fusion of gametes, which leads to the formation of a zygote.

5. **Final Answer**: Therefore, the correct answer to the question is that fertilization is related to the fusion of gametes.

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