**Mitochondria in Sperm**

Mitochondria are present in the middle piece of the sperm. This is an important feature of the sperm cell as mitochondria play a crucial role in providing energy for sperm motility and other cellular processes.

**Explanation:**

1. **Structure of Sperm:** The sperm cell is composed of a head, neck, middle piece, and tail. Each part of the sperm has specific functions. The head contains the nucleus which carries the genetic material (DNA) of the sperm. The neck connects the head to the middle piece, which contains numerous mitochondria. The tail, also known as the flagellum, is responsible for sperm motility.

2. **Function of Mitochondria:** Mitochondria are often referred to as the "powerhouses" of the cell because they generate the majority of cellular energy in the form of adenosine triphosphate (ATP) through a process called oxidative phosphorylation. ATP is the primary energy source used by cells to carry out various functions, including movement.

3. **Role in Sperm Motility:** Sperm cells require a significant amount of energy to swim through the female reproductive tract and reach the egg for fertilization. The mitochondria in the middle piece of the sperm provide the necessary energy for the tail to move in a whip-like motion, propelling the sperm forward.

4. **High Energy Demand:** The middle piece of the sperm contains a high concentration of mitochondria compared to other regions of the cell. This is because sperm cells need a larger supply of ATP due to their specialized function of long-distance swimming.

5. **Inheritance of Mitochondria:** It is worth noting that mitochondria have their own DNA, known as mitochondrial DNA (mtDNA), which is separate from the nuclear DNA in the sperm head. During fertilization, only the nuclear DNA from the sperm is contributed to the zygote, while the mitochondria are solely inherited from the mother's egg.

To summarize, mitochondria are present in the middle piece of the sperm. They are responsible for providing energy for sperm motility, which is essential for successful fertilization.