Puberty — the ability to bear children. Around the age of 11 to 13 years old boys in a certain area of the brain — the hypothalamus — begins to produce special hormone— GnRH. And its entry into the body of the child first comes only at night during deep sleep. But as puberty secretion (release of the hormone) is no longer dependent on the phases of sleep and more often seen in the daytime. At this point, we can talk about the occurrence of sexual maturity in the boy.
GnRH, in turn, by means of two other hormones stimulate spermatogenesis — the formation of sperm and the degree androgens— The male sex hormones.
Under the influence androgens musculature boy becomes heavier, and increases in bone protein content. All this eventually causes an increase in body size. This process happens not gradually but in jumps. Maximum growth boys occurs between 12 and 15.5 years and may reach 10 cm and over a year. After 18 years, the young man could still grow by about 3 cm At one point, a high level of androgens becomes the cause of ossification of the growth zones of long bones, and their further extension stops.
It should be understood that each person develops individually, and two different teen can achieve the same growth to a different age.
Child sexual organs develop in a certain sequence. Please increase the size of the scrotum and testicles, is growth the penis, increasing the seminal vesicles and prostate gland. The first ejaculation occurs approximately between 12.5 and 14 years.
Some boys may temporarily develop gynecomastia — breast augmentation, but within a year it takes place.
Under the influence of testosterone develop male pattern hair. First, grow hair in the pubic area, and in a couple of years on the face and underarms.
Androgens also stimulate the development of the "Adam's apple" — the cartilage of the larynx, and lengthening