Fertilization • During fertilization, egg and sperm fuse, producing a cell with 46 chromosomes (22 pairs of autosomes and 1 pair of sex chromosomes)• The sperm determines the sex of the embryo – If the sperm that fertilizes the egg has an X chromosome, the embryo will be XX (female) – If the sperm that fertilizes the egg has a Y chromosome, the embryo will be XY (male)22+X 22+X XX XY 22+X 22+Y
Chromosomal sex differentiation• Sex chromosomes contain “master switch” genes that initiate a sequence of events leading to development of male or female gonads – Y chromosome: SRY gene, acts to promote male reproductive differentiation. – X chromosome: DSS gene (region that may contain several genes, still being researched), acts to promote female reproductive differentiation.
Gonadal differentiation• Gonads: male and female sex glands (ovaries and testes). – Male and female gonads are the same until about 6 weeks after conception. – Genetic signals determine whether the gonads will develop into ovaries or testes. – After the testes or ovaries develop, they begin releasing sex hormones that continue the process of sexual differentiation.
Differentiation of internal structures• Internal structures: Mullerian or Wolffian duct systems develop into female or male internal organs – Testes secrete androgens that stimulate the Wolffian ducts to develop into vas deferens, seminal vesicles, and ejaculatory ducts – Testes also secrete Mullerian inhibiting substance (MIS) that causes Mullerian ducts to shrink and disappear in males. – In females, absence of androgens causes Mullerian ducts to develop into fallopian tubes, uterus, and inner part of vagina, and the Wolffian duct system degenerates.
Differentiation of internal structures Androgens Mullerian Inhibiting Substance
Differentiation of external structures• Like internal structures, remain undifferentiated until the gonads begin releasing hormones in sixth week of development.• In response to dihydroxytestosterone (DHT), a testosterone product: – the labioscrotal swelling becomes the scrotum. – the genital tubercle becomes the glans of the penis. – the genital folds become the shaft of the penis.• In absence of testosterone, and possibly under influence of a substance triggered by the DSS gene: – Labioscrotal swelling becomes the labia majora. – The genital tubercle becomes the clitoris. – The genital folds become the labia minora.
Differentiation of external structures & labia minora)
Sex differences in the brain• Thought to be “primed” by exposure to hormones in utero.• Male brain approximately 15% larger due to influence of androgens – However, these size differences diminish w/age b/c men’s brains seem to lose neural tissue faster than women’s brains• Hypothalamus – In females, will develop estrogen-responsive cells that regulate the secretion of hormones by the pituitary gland that control the menstrual cycle. – Some differences in the size of specific regions of the hypothalamus
Parts of the brainFig3.4 Parts of the brain: (a) cross section of the human brain showing the cerebralcortex, corpus callosum, hypothalamus and pituitary gland (b) top view showing theleft and right cerebral hemispheres. Only the cerebral cortex covering the twohemispheres is visible.
Sex differences in the brain• Cerebral hemispheres: the two sides of the cerebrum, the largest part of the brain.• Cerebral cortex: outer layer of the cerebral hemispheres, responsible for higher mental processes. – Cerebral cortex in the right hemisphere tends to be thicker in male brains than in female brains. – Women tend to use both brain hemispheres when performing verbal and spatial tasks, while men tend to use only one hemisphere for each of these functions.• Corpus callosum: broad band of nerve fibers that connects the two cerebral hemispheres. – Thicker in women; supposedly allows for > intercommunication btwn. the two cerebral hemispheres – women exhibit less brain function impairment after damage to one cerebral hemisphere.
Can sex differences in the brain explainsex differences in cognitive functioning?• (some examples): – Female scores on verbal skill tests somewhat higher than males. – Males test somewhat higher than females on spatial tests.• Some believe this is a result of differences in cerebral hemispheres & corpus callosum.• Many believe this is largely due to psychosocial factors. – Differences in cognitive functioning between males and females has declined sharply in recent years. – A 1992 study showed that girls start school with math and science abilities equal to boys, but fall behind boys by the time they complete high school; this achievement gap had largely disappeared by 1998 (follow-up study). – When female subjects were provided with a few hours of training in spatial skills, they performed as well as males on tests of these skills.
Gender Identity Formation as a biological processTable 3.1 Gender Identity as a Biological Process: Typical Prenatal Differentiation
Gender Roles• Differ across cultures – Margaret Mead, landmark 1935 book studied gender roles in three cultures in New Guinea • Arapesh culture: both men & women appeared to be mild-mannered, lacking in libido (i.e. “feminine”) • Mundugumor culture: both sexes seemed aggressive &‘highly sexed.’ (i.e. “masculine”) • Tchambuli culture: women dominant, men emotionally dependent (approximate reversal of our gender roles)• Can change over time within a culture – Dad staying home w/kids & mom working may have been ridiculed in 1950s, not considered odd today. – More women are entering formerly male-dominated occupations
The Girl Child forms of discriminationFemale Infanticide: The murder of a female infant. Itoccurs often as a deliberate murder or abandonment ofa young girl or infant.Selective Abortion: Also called gender-selectiveabortion, sex-selective abortion, or female feticide-selective abortion. It involves the abortion of a fetusbecause it is a girl. Many women from communities orcultures with a preference for boys practice selectiveabortion.
The Girl Child forms of discriminationFemale Genital Cutting (FGC): The practice that involvesthe removal or the alteration of the female genitalia. It is acenturies-old practice found in many countries amongpeople from various religions and beliefs, most prevalentin Africa.Honor Killing: The practice of killing girls and womenwho are perceived to have dishonored a family’sreputation by allegedly engaging in sexual activity or otherimproprieties before or outside of marriage. ‘Improper’behavior justifies grounds for killing. It has expanded toinclude transgressions, which are not initiated by the girl,including rape and incest.
The Girl Child facts and statistics Currently, 60 million girls are reported as “missing” as a result of infanticide, sex selective abortions, and neglect. At least 130 million girls alive today have undergone Female Genital Mutilation, and 2 million more are at risk every year. at least 5,000 women & girls are murdered each year for “honor’s sake” by members of their own families. U .N, national reports & studies by NGO s repeatedly show that girls, as a group, have lower literacy rates, receive less health care, & more impoverished than boys. Source: Youth Advocate Program International: www.yapi.org Source: Youth Advocate Program International: www.yapi.org Source: United Nations Children’s Fund: www.unicef.org Source: Amnesty International: www.amnesty.org
How do we form our gender identities?• Gender identity--how we come to think of ourselves as male or female--is formed from• 1) Biology – Prenatal differentiation • Chromosomes, internal reproductive structures, external genitals, hormones, brain development• 2) Socialization – How the family and the culture in which we grow up influence our sense of femaleness or maleness.
Development of social gender identity• 2-3 years old: children can “name” their gender, but most don’t really know what it means. – Don’t know that gender is constant (i.e. that a little boy can’t grow up and have a baby one day)• Around 4-5 years old: children embrace gender, start experimenting with stereotypical objects and behaviors. – This is part of how kids try to grasp gender constancy--by behaving as expected for – their gender, so that their – gender doesn’t “change.”• By 7-8 years old: children• can accept that gender roles• are not rigid if they’ve been• previously exposed to• nonstereotypical ideas about• gender.
Social-Learning Influences on Gender Identity• Parents and people in general have preconceived ideas about how boys and girls behave even before a baby is born.
Social-Learning Influences on Gender Identity• Social-learning theory: suggests that identification with masculine, feminine, or androgynous roles results primarily from the sociocultural influences we are exposed to during our early development.• Gender role expectations strongly influence the environment in which the child is raised. – Color of the room, toy selection, etc. – How parents respond to children (i.e. boy encouraged to suppress tears, be independent, even aggressive (“boys will be boys”); girl may be encouraged to be nurturing and cooperative)
Evidence for social-learning model of gender identity formation• 1) Anthropological studies: gender identity is not fixed across cultures. – Some cultures have masculine and feminine gender roles that are reversed from the typical gender roles, yet there is no biological difference. – Margaret Mead’s studies from 1930s.• 2) Gender role expectations change over time. – Therefore, social learning must make some contribution to gender identity, since men and women aren’t changing biologically.
Interactional Model• Gender is a product of both biology and social learning/environment. – Evidence indicates that infants are not psychosexually neutral at birth and have a biological predisposition toward a male or female identity. – Gender identity is not exclusively biological--life experiences play an important role in shaping our identities.
How do we learn gender roles?• Socialization: the process by which our society conveys behavioral expectations to the individual.• Five agents of socialization – peers influence how child plays – school teachers and textbooks – parental expectations – television and gender-based stereotypes – religious training
Parents as shapers of gender roles• Encouragement of gender-typed play activities and household chores.• Modeling gender-typed behaviors. or
Parents as shapers of gender roles• Baby girls often receive more attention than baby boys do.• Baby girls often treated as fragile.• Girls may be comforted when they cry; boys may be told that “boys don’t cry.”• Parents are more protective and restrictive of girls; boys receive more freedom.• Boys receive parental encouragement for being assertive and limiting emotional expression; girls are rewarded for positively interacting with others.
Schools & educational environment• Research suggests that girls and boys receive different treatment in the classroom. – Teachers call on and encourage boys more. – Boys who call out answers w/o being recognized aren’t usually punished, but girls are. – Teachers tolerate bad behavior in elementary school boys more than girls. – Boys are more likely to receive attention, help, and praise from teachers. – Teachers give girls more attention when they act dependently, but give boys more attention for acting independently or assertively. – Girls frequently suffer a loss of confidence in their math and science abilities in middle school years (around adolescence/puberty).
Organized religion & gender roles• Jewish, Christian, and Islamic traditions – Emphasis on male supremacy – God presented as male using language as Father, He, or King Ex: biblical concept of Eve as created from Adam’s rib shows endorsement that females are secondary to males.• Leadership of most religious organizations is mostly male – No female Protestant clergy until 1970. – No female rabbis until 1972. – Roman Catholic church still does not allow female priests.• There are current movements to change traditional patriarchal nature of organized religion – More females becoming religious leaders. – Efforts to reduce sexist language in religious writings (I.e. replace “God the Father” w/“Creator;” replace “mankind” with “humanity;” replace “sons of God” w/”children of God.”
Television & gender stereotypes• Men appear as active, intelligent, adventurous, in charge. – More emphasis placed on the character’s abilities.• Women appear as passive, less competent, more domestic. – More emphasis placed on the character’s appearance.• Television industry is gradually improving – Better than it was in the 1950s – Still far from gender-neutral.
Impact of gender role expectations on our sexuality• Women as undersexed, men as oversexed – Mistaken belief that women don’t want sex or don’t enjoy sex as much as men.• Men as initiators, women as recipients – Idea that men should initiate sex (could be the first time, or even after years together).• Men as “sexperts” – Idea that men know what to do, that they don’t need to ask women, and that women shouldn’t make suggestions.• Women as controllers, men as movers – Especially in adolescent years, women are “supposed” to pay more attention to regulating “how far the guy gets” than to her own sexual enjoyment.• Men as unemotional and strong, women as nurturing and supportive (“men lust, women love”)
• The health of adolescents is to a large extent determined by family environments that provide the immediate basic needs for shelter, food ,education, health care & spiritual values necessary for character building as well as by school environment
Taking Oath I am the custodian of my mind, body and soul.I will preserve it, protect it and enhance it.
Need for Adolescent clinics• Most vulnerable group to reproductive & sexual health problems• Guarantee privacy & confidentiality & promote autonomy• Safe environment at convenient location& convenient working hours• Adolescent friendly Health care providers who are technically competent & with good communication skills
Exercise is Important• Improves strength & endurance• Helps build healthy bone & muscles• Helps control weight & menstrual problems• Reduces anxiety & stress & increases self esteem• About 60 mts a day of physical activity needed to prevent weight gain
Practical Tips to communicate with adolescents• See them by themselves as well as with their parents• Let adolescents say what they want to say• Show genuine interest in them• Be empathetic respectful & nonjudgemental• Assure confidentiality• Explain concepts in a manner appropriate to their development
• In the end…Make them aware.• Relax !• “Believe it or not, the adults you know have been through the same hang-ups too- Although they might have forgotten how difficult or confusing growing up can be”
Nothing in life is to be feared. It is only to be understood Marie curie
“It requires greaterintelligence to solve theproblem than it took toreach the problem.” Albert Einstein