The document summarizes the male reproductive system. It describes the seminal vesicles as two sac-shaped glands that produce and store seminal fluid and sperms before ejaculation. The seminal fluid supplies nutrients to sperms and helps their mobility. It also describes the prostate gland, located below the urinary bladder, as surrounding the start of the urethra. The prostate neutralizes acid in the urethra and blocks urine during ejaculation.