where the sperm comes from.

Sperm is produced by the testis in the scrotum. There are two important types of cells in the testis: spermatogenic cells and Sertoli cells. After sperm production, they reach the seminal vesicles through the sperm transfer egg and are stored in the seminal vesicles.

After the spermatogenic cells divide continuously, they gradually develop into spermatogonia, primary spermatocytes, secondary spermatocytes, sperm cells, and finally sperm. Sertoli cells mainly protect nerve cells and supply oxygen and nutrients to maintain normal spermatogenic function. After sperm formation, they further mature in the epididymis and mix with seminal plasma to become semen.