Process of fusion of haploid cells is

Options

A. cell cycle
B. meiosis
C. mitosis
D. syngamy

Answer

**Step-by-Step Solution:**

1. **Understanding the Concept of Fusion of Haploid Cells**: The fusion of haploid cells refers to the process where two haploid cells come together to form a new cell. In biological terms, this process is crucial for sexual reproduction.

2. **Identifying the Type of Cells Involved**: In sexual reproduction, the two haploid cells involved are known as gametes. There are two types of gametes: male gametes (sperm) and female gametes (egg or ovum).

3. **Understanding Fertilization**: The specific process through which these two gametes fuse is called fertilization. During fertilization, the male and female gametes unite to form a diploid cell called a zygote.

4. **Recognizing the Terminology**: The term "syngamy" is often used synonymously with fertilization. Syngamy specifically refers to the fusion of two gametes.

5. **Eliminating Incorrect Options**: In the context of the question, other processes such as the cell cycle, meiosis, and mitosis are related to cell division, not the fusion of cells. Therefore, they do not apply to this question.

6. **Conclusion**: The correct term for the fusion of haploid cells is "syngamy," which is synonymous with fertilization.

**Final Answer**: The process of fusion of haploid cells is called **syngamy** (fertilization).

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