The primary egg membrane of mammalians egg is termed as -

Options

A. Zona pellucida
B. corona radiata
C. shell
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of the primary egg membrane of mammalian eggs. In mammals, the egg is known as the ovum, which is the female gamete.

2. **Identifying the Structure of the Egg**: The mammalian egg (ovum) consists of several components:
- **Nucleus**: Contains the genetic material.
- **Cytoplasm**: The fluid that fills the cell.
- **Plasma Membrane**: The outermost layer of the egg cell.

3. **Recognizing the Protective Layers**: The ovum is not left unprotected. It has additional layers that serve as protective membranes:
- The **first protective layer** surrounding the ovum is crucial for its function and is known as the primary egg membrane.

4. **Naming the Primary Egg Membrane**: The primary egg membrane of the mammalian egg is specifically called the **zona pellucida**. This layer is essential for various functions, including sperm binding and fertilization.

5. **Additional Protective Structures**: Beyond the zona pellucida, there are additional layers:
- The **corona radiata**, which consists of multiple cells that provide further protection to the ovum.

6. **Final Answer**: Therefore, the primary egg membrane of mammalian eggs is termed as **zona pellucida**.

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