human growth and development l.
Skip this Video
Loading SlideShow in 5 Seconds..
Human Growth and Development PowerPoint Presentation
Download Presentation
Human Growth and Development

Loading in 2 Seconds...

play fullscreen
1 / 33

Human Growth and Development - PowerPoint PPT Presentation

  • Uploaded on

Human Growth and Development. Chapter Fourteen Adolescence: Biosocial Development. PowerPoints prepared by Cathie Robertson, Grossmont College Revised by Jenni Fauchier, Metropolitan Community College. Puberty Begins. Period of rapid physical growth and sexual maturation

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Human Growth and Development' - corin

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
human growth and development

Human Growth andDevelopment

Chapter Fourteen


Biosocial Development

PowerPoints prepared by Cathie Robertson, Grossmont College

Revised by Jenni Fauchier, Metropolitan Community College

puberty begins
Puberty Begins

Period of rapid physical growth and sexual maturation

typically completed three to four years after first visible signs

Person attains adult size, shape, and sexual potential

Puberty begins with hormone production in brain

hormones from hypothalamus trigger production in pituitary glands

in turn this triggers hormone production in adrenal glands and sex glands (gonads)

To regulate body functions and changes, many hormones follow this route, the HPA (hypothalamus/pituitary/adrenal) axis

At puberty, the pituitary gland activates the gonads, or sex glands (ovaries in females, testes in males)

One hormone in particular, GnRH, causes increased production of estrogen in females and testosterone in males

Hormones, cont.

direct effects on emotions
Direct Effects on Emotions

Rapidly increasing hormone levels precede rapid arousal of emotions

Hormonal levels correlate with quick shifts in emotional extremes

For boys this increase precipitates thoughts about sex and masturbation

For girls hormonal changes during menstrual cycle produce mood changes

indirect effects on emotions
Indirect Effects on Emotions

Hormone levels produce visible signs of sexual maturation, which in turn create expectations of new maturity

social responses to biological signs trigger adolescent moods and reactions

One’s culture affects thoughts of sex

first sexual intercourse occurs at different ages in different cultures

the timing of puberty
Normally, body changes begin to appear between ages 8 and 14

It’s hard to prepare without knowing what changes will be and when they’ll appear

individual may grow a little taller and put on some weight

The Timing of Puberty
sex genes and weight
Sex, Genes, and Weight

Girls on average are about two years ahead of boys

Menarche and spermarche

Timing can be affected by genetics, ethnicity, and body fat

individuals with stockier builds experience puberty earlier

chronic malnutrition limits fat, thus delaying puberty by several years

stress in families
Stress in Families

Family conflict may cause earlier onset of puberty or irregular periods

stress levels affect hormone production

stress probably affects hormones causing puberty

Stress hypothesis gained support when researchers identified two factors influencing early puberty

conflicted relationships with family

unrelated man living in the home

too early or too late
Too Early or Too Late

Early-maturing girl may be teased and is embarrassed

Age of menarche is a strong predictor of age at first intercourse

Late-maturing boys may be shunned

Early-maturing boys are socially popular and often sports heroes

too early or too late cont
Too Early or Too Late, cont.
  • Low self-esteem of off-time maturation lingers
  • Early-maturing girls become mothers sooner
  • Late-maturing boys marry later and are less likely to be leaders
wider taller then stronger
Increase occurs in bone length and density

feet and fingers lengthen, then arms and legs, then torso

Weight gain becomes rapid

Height increase follows

Timing: for girls, 10–14; for boys, 12–16

Wider, Taller, Then Stronger
other body changes
Other Body Changes

Organ growth

torso grows as internal organs grow

lungs triple in weight and size (breathing rate decreases)

heart doubles in size (heart rate decreases), total volume of blood increases

physical endurance in exercise increases

lymphoid system decreases in size

hormones may cause changes in oil, sweat, and odor glands of the skin

eyes change—may cause nearsightedness

primary sex characteristics
Primary sex characteristics—parts of the body that are directly involved in reproduction: vagina, uterus, testes, penis

Primary sex organs grow

girls: uterus grows, vaginal lining thickens

menarche—first menstrual period

boys: testes, penis, scrotal sac enlarge

spermarche—first ejaculation of seminal fluid

Primary Sex Characteristics
secondary sex characteristics

Secondary sex characteristics—body characteristics not directly involved in reproduction but indicating sexual maturity


females accumulate fat

in both sexes, diameter of areola around nipples increases

    • voice lowers, especially in males
    • body hair becomes coarser and darker
    • new hair growth in armpits and in genital area
hazards to health
Adolescence is generally healthy time

Minor childhood illnesses less common; major adult diseases rare

Health of adolescents is more likely to be harmed by their own actions

Hazards to Health
poor nutrition
Need for good, healthy calories is greater due to growth spurt

many adolescents become fat and flabby—due not to excess food, but lack of exercise

Adolescents generally eat enough but not the right foods

snack with friends

too much fat, sugar, empty calories; too little calcium

Poor Nutrition
poor nutrition cont
Poor Nutrition, cont.
  • only one in five U.S. high school seniors consumes RDI of five servings of fruits and vegetables
  • inadequate milk consumption is troubling, as calcium is major contributor to bone growth
    • one-half adult bone mass acquired during adolescence
poor nutrition cont21
Poor Nutrition, cont.
  • fewer than half of all teenagers consume RDI of iron
    • females do not get enough iron, while menstrual cycle depletes iron; therefore, may become anemic
poor nutrition cont22
Poor Nutrition, cont.
  • Nutritional deficits sometimes arise from distorted body image
    • Body Image—person’s concept of how his or her body appears
    • developing a healthy body image is an integral part of becoming an adult
      • negative-self appraisal has a major impact on self-esteem
sex too soon
With puberty occurring earlier than it used to in the United States, and marriage later, long period between first sexual urges and marriage

More than 25 percent of teens are sexually active by age 14; about one-half active by high school graduation

Sex Too Soon
sexually transmitted diseases
Sexually active teenagers have higher rates of most common STDs—gonorrhea, genital herpes, syphilis, and chlamydia—than any other age group

Risk of exposure to HIV virus increases if a person is

already infected with other STDs

has more than one partner in a year

does not use condoms during intercourse

Sexually Transmitted Diseases
teenage pregnancies
Younger adolescents within two years of beginning menarche are at increased risk for many complications because their bodies have not matured

risks include spontaneous abortion, eclampsia, stillbirth, C-section, low birth weight

women who have given birth before age 16 tend to be shorter and sicker as adults and live less long

Teenage Pregnancies
teenage pregnancies cont
Teenage Pregnancies, cont.
  • Older adolescents are at less physical risk but have their own set of problems
    • after birth of baby, educational and vocational achievement slowed down
    • babies have a higher risk of prenatal and birth complications than other babies
    • problems are linked to culture and cohort
sexual abuse
Sexual Abuse

Defined as the use of unconsenting person for one’s own sexual pleasure

Child sexual abuse—activity that arouses the adult and excites, shames, or confuses a person under age 16

abusers of adolescent girls—usually male relative or friend

abusers of adolescent boys—usually male not in family

drug use and abuse
Drug abuse—ingestion of drug so that it impairs user’s well-being

Drug addiction—dependence on a drug or behavior that makes user feel physically or psychologically at ease

Drug use—ingestion of a drug regardless of amount or effect

Nations differ considerably in use

in-laws and culture influence usage

religion influences usage

Drug Use and Abuse
the gateway drugs
Link between their occasional use and later drug abuse and addiction repeatedly found

characteristics: violence, early sexual activity, and school failure

drug use both cause and symptom of adolescent problem

The Gateway Drugs
the gateway drugs cont
The Gateway Drugs, cont.
  • Tobacco
    • decreases food consumption
    • interferes with absorption of nutrients
    • reduces fertility
    • most physically addictive drug of all
  • Alcohol
    • more harmful in adolescence
    • correlates with abnormal brain development
the gateway drugs cont31
The Gateway Drugs, cont.
  • Marijuana
    • seriously slows down thinking processes, especially memory and abstract reasoning
    • may cause lack of motivation and indifference toward future
patterns of adolescent drug use
Almost every teenager tries one of the gateway drugs

by high school graduation, most have tried all three

experimentation happening earlier than previously

Experimentation and regular use

daily use and abuse increases throughout late adolescence

Patterns of Adolescent Drug Use
cultural differences in drug use
National culture makes a difference

In Europe, adolescents show increased drug use

adolescent girls in United States as likely to smoke as adolescent boys; in Asia and African few women smoke

drug use changes in frequency, composition, mode of delivery, and in form

Cultural Differences in Drug Use