The male reproductive system is a system that is made up of organs that work together to bring about the production of steroid hormones (testosterone, luteinizing hormones and follicle stimulating hormones) through steroidogenesis, spermatozoa through a process called spermatogenesis, transportation of the formed spermatozoa and storage of the spermatozoa. The system basically is made up of the penis (copulatory organ) and a pair of testes hanging outside the body and housed in the scrotum. There are also other organs which secrete various substances that mix with the sperm to produce a mixture we regard as semen. These other organs are the seminal vesicle which produces a sticky yellowish fluid that contains fructose and contributes about 70% of the semen, the prostate gland which produces a milky substance that contains calcium and the bulbourethral gland which produces a clear and slippery fluid that lubricates the urethra. The epididymis and the vas deference serve as transportation/temporary storage site and a permanent storage site respectively for the sperm.