Fertilization membrane in ovum prevents

Options

A. Meiosis - II
B. polyspermy
C. Meiosis - I
D. phase of Multiplication

Answer

### Step-by-Step Solution:

1. **Understanding the Fertilization Membrane**:
- The fertilization membrane is a protective layer that forms around the ovum (egg) immediately after fertilization occurs. This layer is also known as the vitelline membrane.

2. **Formation of the Fertilization Membrane**:
- This membrane is created when a sperm cell successfully fuses with the egg cell. The fusion triggers a series of biochemical reactions that lead to the formation of the fertilization membrane.

3. **Function of the Fertilization Membrane**:
- The primary function of the fertilization membrane is to prevent multiple fertilizations. This is crucial because if more than one sperm were to fuse with an egg, it could lead to a condition known as polyspermy.

4. **Understanding Polyspermy**:
- Polyspermy occurs when more than one sperm enters an egg. This can result in abnormal development of the embryo, as the genetic material from multiple sperm can disrupt normal fertilization processes.

5. **Conclusion**:
- Therefore, the fertilization membrane acts as a barrier to ensure that only one sperm can fertilize the egg, thus preventing polyspermy.

### Final Answer:
The fertilization membrane in the ovum prevents **multiple fertilization** (or polyspermy).

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