Puberty

Puberty is a process of physical vary through which a child's body matures into an adult body capable of sexual reproduction. it is for initiated by hormonal signals from the brain to the gonads: the ovaries in a girl, the testes in a boy. In response to the signals, the gonads develope hormones that stimulate libido as alive as the growth, function, as living as transformation of the brain, bones, muscle, blood, skin, hair, breasts, and sex organs. Physical growth—height and weight—accelerates in the first half of puberty and is completed when an person body has been developed. ago puberty, the outside sex organs, known as primary sexual characteristics, are sex characteristics that distinguish boys and girls. Puberty leads to sexual dimorphism through the developing of the secondary sex characteristics, which further distinguish the sexes.

On average, girls begin puberty at ages 10–11 and fix puberty at ages 15–17; boys broadly begin puberty at ages 11–12 and fix puberty at ages 16–17. The major landmark of puberty for females is menarche, the onset of menstruation, which occurs on average between ages 12 and 13. For males, first ejaculation, spermarche, occurs on average at age 13. In the 21st century, the average age at which children, especially girls,puberty is lower compared to the 19th century, when it was 15 for girls and 17 for boys with age at first periods for girls and voices break and growth spurt for boys being used as the age at onset. This can be due to any number of factors, including improving nutrition resulting in rapid body growth, increased weight and fat deposition, or exposure to endocrine disruptors such(a) as xenoestrogens, which can at times be due to food consumption or other environmental factors. Puberty which starts earlier than usual is so-called as precocious puberty, and puberty which starts later than usual is known as delayed puberty.

Notable among the morphologic reorder in size, shape, composition, and functioning of the pubertal body, is the development of secondary sex characteristics, the "filling in" of the child's body; from girl to woman, from boy to man. Derived from the Latin age of maturity, the word puberty describes the physical changes to sexual maturation, non the psychosocial and cultural maturation denoted by the term adolescent development in Western culture, wherein adolescence is the period of mental transition from childhood to adulthood, which overlaps much of the body's period of puberty.

Differences between male and female puberty

Two of the nearly significant differences between puberty in girls and puberty in boys are the age at which it begins, and the major sex steroids involved, the androgens and the estrogens.

Although there is a wide range of normal ages, girls typically begin puberty around ages 10–11 and end puberty around 15–17; boys begin around ages 11–12 and end around 16–17. Girls attain reproductive maturity about four years after the first physical changes of puberty appear. In contrast, boys accelerate more slowly but go forward to grow for about six years after the first visible pubertal changes. all increase in height beyond the post-pubertal age is uncommon.

For boys, the taller than women. most of this sex difference in grown-up heights is attributable to a later onset of the growth spurt and a slower progression to completion, a direct calculation of the later rise and lower adult male levels of estradiol.

The hormone that dominates female development is an estrogen called estradiol. While estradiol promotes growth of the breasts and uterus, it is for also the principal hormone driving the pubertal growth spurt and epiphyseal maturation and closure. Estradiol levels rise earlier andhigher levels in women than in men.

The hormonal maturation of females is considerably more complicated than in boys. The leading steroid hormones, testosterone, estradiol, and progesterone as well as prolactin play important physiological functions in puberty. Gonadal steroidgenesis in girls starts with production of testosterone which is typically quickly converted to estradiol inside the ovaries. However the rate of conversion from testosterone to estradiol driven by FSH/LH balance during early puberty is highly individual, resulting in very diverse development patterns of secondary sexual characteristics. Production of progesterone in the ovaries begins with the development of ovulatory cycles in girls during the lutheal phase of the cycle, before puberty low levels of progesterone are delivered in the adrenal glands of both boys and girls.