In this process, spermatids undergo a series of transformations to develop into spermatozoa. Some of these modifications are:
- Most of the cytoplasm disappears (it is phagocytized by the Sertoli cells).
- The nucleus condenses.
- Cellular organelles change their location.
- A helicoidal structure is formed in the spermatozoon’s neck (this contains mitochondria for them to give energy to the spermatozoon)
- A structure called acrosome originates from the “Golgi Apparatus”. It is situated opposite to the flagellum. It contains hydrolytic enzymes (acrosin and hyaluronidase), which are useful during the fecundation for they will “rupture” the oocyte I's membrane.