Unit 2 Flashcards
Physical development in adolescence
Which 3 forces combine to influence adolescent development?
Biological, psychological and social forces
what are biological changes?
universal changes in the body (found in all primates and all cultures)
what are some internal stresses and social expectations adolescents face?
- giving up childish ways
- developing new interpersonal relationships
- taking on greater responsibility
What are internal stresses and social expectations in adulthood likely to prompt?
moments of uncertainty, self-doubt and disappointment in all teenagers
How does adolescence length vary among cultures?
It varies substantially among cultures, with tribal and village societies having a brief intervening phase, while industrialized nations have an extended adolescence.
What are the three phases of adolescence in industrialized nations?
Early adolescence: 11-14 years (rapid pubertal change)
Middle adolescence: 14-16 (pubertal changes nearly complete)
Late adolescence: 16 - 18 (full adult appearance, anticipation of adult roles)
At what age does rapid pubertal change occur?
during early adolescence from 11 - 14 years
When are pubertal changes nearly complete?
during middle adolescence from 14 - 16 years
When does a young person achieve full adult appearance?
In late adolescence, from 16 - 18 years
What is puberty?
it refers to the years of rapid physical growth and sexual maturation that end childhood
-> person of adult size, shape and sexuality
what unleashes the forces of puberty?
a cascade of hormones
what do the cascade of hormones during puberty produce?
external growth, internal changes
-> including heightened emotions and sexual desires
what happened over the past decades to the age of puberty?
it decreased
is there a difference between the time girls and boys reach puberty?
yes, girls reach puberty on average two years earlier
What are some of the observable changes through puberty for girls?
- usually begin with nipple growth
- pubic hair
- peak growth spurt
- widening of the hips
- first menstrual period
- full breast growth
How do you call the first menstrual period of a girl?
Menarche
What does the Menarche signal?
that the girl has begun ovulation
is a pregnancy possible after the first period?
biologically yes, but ovulation and menstruation are often irregular for years after menarche
What is the average age for menarche?
about 12 years and 4 months
-> variation in time is quite normal
What are some of the observable changes through puberty for boys?
- growth of the testes
- initial pubic hair growth
- growth of penis
- first ejaculation of seminal fluid
- appearance of facial hair
- peak growth spurt
- deepening of the voice
- final pubic hair growth
What is the first ejaculation of sperm called?
Spermarche
When does a boy start having erections?
in early infancy, but ejaculation signals sperm production
how may the spermache occur?
during sleep in a ‘wet dream’ or via direct stimulation
What is the typical age of spermache?
just under 13 years, almost a year later than menarche
When does puberty typically begin?
between 8 and 16
how long does the entire process of puberty usually take?
about seven years
does the sequence of puberty vary between individuals?
no, the sequence of puberty is usually the same for everyone, though the timing varies widely.
Which axis do many hormones regulating puberty follow?
the HPA (hypothalamus-pituitary-adrenal) axis
What is the role of the HPG axis in puberty?
It regulates the enlargement of gonads and increases the production of sex hormones during puberty.
Which hormone causes the gonads to enlarge and dramatically increase their production of sex hormones?
GnRH (gonadotropin-releasing hormone)
What are the typical hormones in boys and girls?
boys: testosterone
girls: estradiol
what are estrogens (including estradiol)?
female hormones
what are androgens (including testosterone)
male hormones
do androgens only occur in girls and androgens only in boys?
no, both sexes have some of both
what do the activated gonads produce?
sperm or ova, released in menarche or spermarche
what does menarche and spermache indicate?
that conception is possible
what is the growth spurt?
rapid gain in height and weight
when is growth in body size usually completed?
for girls by age 16 and for boys by age 17 1/2
what reverses during puberty?
the cephalocaudal growth
what is cephalocaudal growth?
pattern of growth that occurs from head to toe
what does it mean that the cephalocaudal growth reverses?
the hands, legs, and feet accelerate first, followed by the torso
what does the pattern of reversed cephalocaudal growth explain?
why early adolescents often appear awkward and out of proportion - long legged with giant feet and hands
What are primary sexual characteristics?
they involve the reproductive organs
-> every primary sex organ (ovaries, uterus, penis, testes) increases dramatically in size and matures in function
what is possible by the end of the primary sexual process?
reproduction
what are secondary sexual characteristics?
visible, bodily features
-> no direct affect on reproduction
example: man’s beard and woman’s breast
-> indicate sexual maturity
How does the development of the shape differ between girls and boys?
similar shapes but
- males widen at shoulders and grow approximately 12 cm taller than females.
- girls widen at the hips and develop breasts
are widened hips and breasts required for conception?
no. thus they are secondary sex characteristics
in what sense are secondary sex characteristics important?
psychologically
What contributes substantially to the timing of pubertal changes?
Heredity
how much of the variation in age of puberty is genetic?
about two-thirds
what does genetics in the timing of puberty mean for identical twins?
Identical twins are more similar than fraternal twins in attainment of most pubertal milestones
how do sex chromosomes affect height in adolescents?
Sex chromosomes have a marked effect on height, with average girls being about two years ahead of average boys.
when does the female height spurt occur?
before menarche
when does the male height increase typically happen?
relatively late, after spermarche