The union of male and female reproductive cells or gametes is known as?

Options

A. Fertilization
B. Cross-pollination
C. Self-pollination
D. Biotic pollination

Explanation

**Step-by-Step Solution:**

1. **Understanding Gametes**: Gametes are the reproductive cells in organisms. The male gamete is typically referred to as sperm, while the female gamete is known as an ovum or egg.

2. **Definition of Union of Gametes**: The union of male and female gametes is a crucial process in reproduction. This union leads to the formation of a zygote, which eventually develops into a new organism.

3. **Identifying the Process**: The specific term used to describe the union of male and female gametes is essential to understand. The options provided are:
- Fertilization
- Cross pollination
- Self pollination
- Biotic pollination

4. **Analyzing the Options**:
- **Fertilization**: This is the process where the male gamete fuses with the female gamete.
- **Cross Pollination**: This refers to the transfer of pollen from one flower to another, which is a form of reproduction in plants but does not directly refer to the union of gametes.
- **Self Pollination**: This is when pollen from the same flower fertilizes its ovules. While it involves gametes, it is not the direct term for their union.
- **Biotic Pollination**: This involves the transfer of pollen by living organisms but does not specifically refer to the union of gametes.

5. **Conclusion**: The correct answer to the question is **Fertilization**, as it specifically refers to the process of the union of male and female gametes.

**Final Answer**: The union of male and female reproductive cells or gametes is known as **Fertilization**.

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