Male Sex Organs.

The primary male sex organs are the testes, scrotum, epididymis, seminal vesicles, prostate gland, Cowper's glands, penis, vas deferens, and urethra. They are depicted in the figure below.


A number of important changes occur in these organs during adolescence. The growth of the tetes and scrotum accelerates, beggining at about 11-1/2, becoming fairly rapid by age 13-1/2 and slowing thereafter. These ages are averages. Rapid growth may start between 9-1/2 and 13-1/2 years, ending between ages 13 and 17. During this time, the testes increase 2-1/2 times in length and about 8-1/2 times in weight.

Before puberty the epididymis is relatively large in comparision with the testes; after maturity the epididymis is only about one-ninth the size of the testes.

The various changes in functions of male sex organs are:

  • Spermatogenesis
  • The Development of Penis
  • Cowper's Glands


The most important change within the testes themselves is the develpment of mature sperm cells. This occurs when FSH(Follicle-Stimulating Hormone) and LH(Luteinizing Hormone) from the pituitary stimulate production and growth. The total process of spermatogenesis, from time the primitive spermatogonium is formed until it grows into a mature sperm in about 10 days.

Following spermatogenesis the sperm migrate by contraction of the seminiferous tubules to reach the epididymis where they may remain for as long as six weeks. Sperm are then transported by ciliary action through the epididymis into the vas deferens, eventually reaching the seminal vesicle and prostate gland where they are made more mobile by the addition of the seminal fluid, passing with it through the urethra and out of the penis at each ejaculation. The seminal fluid, a highly alkaline, milky fluid, keeps the sperm alive, healthy, and mobile and serves as a vehicle for carrying the sperm out of the penis.

The Development of Penis

The penis doubles in length and girth during adolescence, with the most rapid growth taking place between ages fourteen and sixteen. genital growth usually takes 3 years to reach the adult stage, but some males complete this development in 1.8 years and others take as many as 4.7 years. In the adult male, the flaccid (limp) penis averages 3 to 4 inches in length and slightly over 1 inch in diameter. The tumescent (erect) penis, on the average, is 5-1/2 to 6-1/2 inches in length and 1-1/2 inches in diameter; sizes vary from male to male.

Size of Penis and Sexual Capability: Adolscent boys are often concerned with the dimensions of their penis, for they associate masculinity and sexual capability with penis size. The size of the erect penis has little to do with sexual capability, for the vaina has few nerve endings, and female excitation comes primarily from stimulation of the external genitalia. The degree of pleasure experienced by both the man and woman has nothing to do with the size of the male organ.Despite what they tell you

Circumcised and Uncircumcised Penis: The head of the penis (glans penis) is covered by a loose fold of skin, the prepuce or foreskin, often removed surgically through circumcision for hygenic or religious reasons. Circumcision is not obligatory health measure today as long as the foreskin can be retracted and the penis is kept clean. If the prepuce is not retracted and the glans washed, a cheeselike substance known as smegma collects, acting as a breeding ground for irritants and disease.

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