The anterior portion of sperm head is covered by a cap-like structure, called acrosome. Acrosome is formed from the Golgi complex. It contains digestive enzyme hyaluronidase and proteinase. It is the capitis covering above the nucleus. It is surrounded by double membrane. Acrosome and its membrane are together called Galea-capatis. Acrosome plays an important role in penetration of ovum by sperm during fertilization.