Fill in the following blanks with suitable words:
d) The process of fusion of gametes is called …………..

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term that describes the process where male and female gametes come together.

2. **Identifying Gametes**: In animals, the male gamete is known as sperm and the female gamete is known as the ovum (or egg).

3. **Defining the Process**: The fusion of these two gametes (sperm and ovum) is a crucial step in reproduction.

4. **Naming the Process**: The specific term used to describe the fusion of gametes is "fertilization".

5. **Conclusion**: Therefore, the blank can be filled with the word "fertilization".

**Final Answer**: The process of fusion of gametes is called **fertilization**.

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