Ch. 8: Adolescence: Physical development

What physical changes occur in girls

For girls the fists signs of puberty is a growth spurt (a dramatic change in height and weight that occurs during puberty averaging about inches), about six months after the growth spurt girls start to develop breasts (which take about 4 years to grow to their adult form) and pubic hair. Menarche (a girls first menstruation) typically occurs in the final stages of breasts and pubic hair development, when growth is winding down. They can get pregnant in this stage but not until the window of infertility closes and the system fully gears up, also the rate at which these changes occur vary across all women.

What are potential problems of early-maturing girls

Having a high BMI (being overweight) foreshadowing later obesity and may even predict when they sexually mature. Due to their outwardly appearing more mature they are more likely to interact with older children and engage in externalizing problems. They also tend to get worse grades than their peers and are also at risk of getting anxious and or depressed.

Adrenal androgens

Hormones produced by the adrenal glands that produce various aspects of puberty, such as growth of body hair, skin changes, and sexual desire.

Primary vs. secondary sexual characteristics

Primary characteristics refer to the body changes directly involved in reproduction. The growth of the penis and menstruation are primary examples. Secondary characteristics refer to hundreds of other changes that accompany puberty, such as breast development, the growth of pubic hair, voice changes, and alterations in the texture of the skin.

What hormonal changes occur in puberty P.1

Starting around 6-8 the first of the two command centers that programs puberty kicks in. Located in the adrenal gland at the top of the kidneys, this process begins several years before children begin to show visible signs of puberty. This process releases Adrenal Androgens, whose output increases to reach a peak at the early twenties, eventually produce (among other events) pubic hair development, skin changes, body odor, and our first feelings of sexual desire.

What physical changes occur in boys

The growth of the penis length and the development of pubic hair are usually first in the stages so boys tend to look much younger on the outside for the first year or to after their bodies begin to develop. Voice changes, the growth of body hair, and that other visible sign of being a man - needing to shave - all take place after the growth of the testes and penis are underway. During their puberty growth spurt boys tend to average almost double the girls at 8 inches, also becoming far stronger than their girl counterparts due to a tremendous increase in muscle mass and dramatic cardiovascular changes. Also boys tend to grow in their feet and legs, and a cracky voice due to the expansion of the larynx.

What is puberty

The hormonal and physical changes by which children become sexually mature beings and reach their adult height.

HPG Axis

The main hormonal system programming puberty; it involves a triggering hypothalamic hormone that causes the pituitary to secrete its hormones, which in turn cause the ovaries and testes to develop and secrete several closely related compounds like estrogens and the hormone testosterone that produce the major body changes. Such as estrogen causing the females changing shape by causing then hips to widen and the uterus and breasts to enlarge, setting in motion the cycle of reproduction causing the ovaries to produce eggs, and the testosterone causing the penis to lengthen and promoting the growth of facial and body hair, the dramatic increase of muscle mass and other internal masculine changes.

Sexual activity

These girls are more likely to have sex early on, and for that sex to be unprotected as they have not yet developed the skills that allows them to resist the social pressure

What hormonal changes occur in puberty P.2

Two years after the adrenal androgens begin to produce the hormones, the most important of the two command centers kicks in. Called the HPG axis because it involves the hypothalamus (in the brain), the pituitary (a gland at the base of the brain), and the gonads (the ovaries and the testes)- this system produces the major body changes.