Its secretion is part of the seminal fluid. The seminal vesicles, a pair of sac-like structures located behind the prostate, are associated with the vas deferens and secrete a thick, yellowish, alkaline fluid which forms the bulk of the semen. The penis is the male genital organ, the organ used during sexual intercourse. It ejaculates the seminal fluid containing the sperm. It is located in front of the scrotum.
Ejaculation is the discharge of semen from the penis.
Impulses from the spinal cord centers cause contractions of the epididymis and vas deferens, which expel sperm into the urethra. Two to four cubic centimeters of semen, containing approximately 300 million sperm, are expelled at each ejaculation. It is the smallest cell in the male body and is continuously produced by the testicles from puberty onward. A sperm cell contains twenty-three chromosomes, including the X or Y chromosome that determines gender. Contributions are tax deductible .