Exam 4 - Adolescents (Chapter 8 & 9) Flashcards
Puberty
The hormonal and physical changes by which children become sexually mature human beings and reach their adult height.
Puberty Rites
A “coming of age” ritual is held in traditional cultures to celebrate children’s transition to adulthood.
Secular trend in puberty
A decline in the average age at which children reach puberty.
Menarche
first menstruation was the signal for celebrating the entrance into womanhood
Spermarche
male signal of fertility, or first ejaculation of live sperm, is a hidden event
HPG Axis
The main hormonal system that programs puberty;
- involves a triggering hypothalamic hormone that causes the pituitary to secrete its hormones
- which in turn causes the ovaries and testes to develop
- secrete the hormones that produce the major body changes.
Adrenal Androgens
Hormones are produced by the adrenal glands that program puberty.
Puberty rites usually involve feelings of
- anxiety
- awe
- self-efficacy
How has the start of puberty changed from the past to today
-
Today:
- starts at 9 or 10
-
Past:
- The 1860s: Over 17
- The 1960s: dropped to 13
Pregnancy age change
in the past girls were not pregnant until their late teens, now before teens
Menarche used as a benchmark for
charting secular trends
nation’s economic development (SES)
Black menstruation pattern
US African American girls begin menstruating at: close to age 12
Impoverished African Countries begin at: over 16
Puberty programmed by
2 command centers
- System 1 - in adrenal glands
- Begins to release hormones at age 6 - 8
- System 2 - HPG axis: Produces major body changes
- Involves hypothalamus, pituitary, and gonads
Puberty set off by
3 phase chain reaction at Age 9 or 10
- Bursts of hypothalamic hormone stimulate the pituitary gland
- Causes ovaries & testes to secrete several closely related compounds called estrogens and testosterone
- Blood concentrations of estrogens and testosterone float upward and unleash physical transformation
Primary Sexual Characteristic
Physical changes of puberty directly involve the reproductive organs, such as the growth of the penis and the onset of menstruation.
Growth spurt
A dramatic increase in height and weight occurs during puberty.
Secondary Sexual Characteristic
Physical changes of puberty are not directly involved in reproduction, such as female breast development and male facial hair.
Testosterone
The hormone is responsible for the maturation of the male reproductive organs and other signs of puberty in men, and for hair and skin changes and sexual desire in both sexes.
Both girls and boys produce
estrogen and testosterone
Mostly Estrogens = females
All Testosterone = male
Responsible for sexual arousal in females and males
- Testosterone
- Adrenal androgens
What primes the triggering hypothalamic hormone?
- Genetics
- Exposure to light
- Chemicals in water
- Food
- Environmental stress
- Leptin
- Body fat
Weight and puberty delays
- Undernutrition = delays puberty
- Obesity = speeds up puberty
A dramatic early sign of puberty in girls
the growth spurt (speed picks up, then decreases )
Breasts and pubic hairs become visible when
6 months after the growth spurt begins