The head of a mature sperm is mainly composed of :-

Options

A. An acrosome
B. Elongated nucleus covered by acrosome
C. Two centrioles and an axial filament
D. Nucleus, acrosome, cytoplasm and mitochondrial shock.

Answer

To answer the question about the composition of the head of a mature sperm, we can break it down into several steps:

### Step-by-Step Solution:

1. **Identify the Structure of the Sperm**:
- The mature sperm consists of three main parts: the head, the midpiece, and the tail (flagellum). The question specifically asks about the head.

2. **Focus on the Head of the Sperm**:
- The head of the sperm is crucial for its function in reproduction. It is primarily involved in delivering genetic material to the ovum.

3. **Components of the Head**:
- The head contains an elongated nucleus. This nucleus is responsible for carrying the genetic information (DNA) from the male parent.

4. **Acrosome**:
- The head is also covered by a structure called the acrosome. The acrosome is a cap-like structure that contains enzymes necessary for penetrating the outer layers of the ovum during fertilization.

5. **Function of the Components**:
- The elongated nucleus is essential for the formation of the zygote after fertilization, as it fuses with the ovum's nucleus. The acrosome, with its lytic enzymes, helps in breaking down the ovum's protective layers, allowing the sperm to enter.

6. **Conclusion**:
- Therefore, the head of a mature sperm is mainly composed of an elongated nucleus covered by the acrosome.

### Final Answer:
The head of a mature sperm is mainly composed of an elongated nucleus covered by acrosome.

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