·  Sex – The biological aspects of being male or female.

·  Gender – The behavioral, psychological, and social characteristics of men and women.


·  Complex organisms reproduce through sexual reproduction, where two parents each donate a gamete or germ cell, which combine to create a new organism.

·  The germ cells from the sperm and from the ovum each contains half of the new person’s genes, which direct the development of the genitals and reproductive organs, and set the biological clock running to trigger puberty, female menopause, and male andropause.

·  Most cells in the human body contain forty-six chromosomes arranged in twenty-three pairs.

·  Twenty-two of the pairs look almost identical and are referred to as autosomes.

·  The two sex chromosomes are made up of an X chromosome donated by the woman’s ovum and either an X or Y chromosome donated by the man’s sperm.

·  If the male contributes an X chromosome, the child will be female (XX), and if it is a Y, the child will be male (XY).

·  During fertilization, a sperm and egg, each containing twenty-three chromosomes (called haploid), join to produce a zygote containing forty-six chromosomes (called diploid). The zygote can now undergo mitosis, cell division, and reproduce its forty-six chromosomes.

·  The forty-six chromosomes are threadlike bodies made up of over 100,000 genes, each of which contains deoxyribonucleic acid (DNA) which acts as a blueprint for how every cell in the organism will develop.

A. Sexual Differentiation in the Womb

·  A human embryo typically undergoes about nine months of gestation.

·  At about four to six weeks, the first tissues that become the embryo’s gonads develop.

1. Internal sex organs

a. Around the fifth to sixth week of gestation the primitive gonads form, which can potentially develop into testes or ovaries.

b. The primitive duct system, the Müllerian duct (female) or the Wolffian duct (male), develop by the tenth or eleventh week.

c. In female embryos, hormones lead to the disappearance of the Wolffian ducts, and the Müllerian duct fuses to form the uterus, the inner third of the vagina, and the Fallopian tubes.

d. In male embryos, the testes begin producing Müllerian inhibiting factor (MIF) and testosterone, which cause the Müllerian ducts to disappear.

2. External sex organs

a. Male and female organs that began from the same prenatal tissue are called homologous.

b. In females, hormones cause the mound of skin beneath the umbilical cord (the genital tubercle) to develop into the clitoris, the labia minora, the vestibule, and the labia majora.

c. In males, androgen stimulates the skin beneath the umbilical cord to develop the penis, the urethra, and the scrotum.

3. Hormonal Development and Influences

a. Endocrine glands, such as the gonads, secrete hormones directly into the bloodstream to be carried to the target organs.

b. The ovaries produce the two major female hormones, estrogen and progesterone.

c. Estrogen is an important influence in the development of female sexual characteristics throughout life, while progesterone regulates the menstrual cycle and prepares the uterus for pregnancy.

d. The testes produce androgen, which influences the development of male sexual characteristics throughout life.

4. Brain Differentiation

a. The brain regulates most hormonal secretions, yet hormones also affect the development of the brain.

b. Female brains control menstruation and must signal the release of hormones in a monthly cycle, whereas male brains signal release of hormones continuously.

B. Atypical Sexual Differentiation

·  Atypical sexual differentiation may be caused by hormone or genetic irregularities and can result in an infant born with ambiguous genitals or external genitals that do not match the infant’s genetic sex.

1. Sex chromosome disorders

a. Klinefelter’s syndrome

·  occurs in about one in 700 live male births

·  an ovum containing an extra X chromosome is fertilized by a Y sperm, resulting in XXY.

·  Men with XXY are infertile, have small testicles, low levels of testosterone, can have gynecomastia, and are tall with feminized boy contours.

·  Testosterone therapy can enhance the development of secondary sexual characteristics.

c. Turner’s syndrome

·  occurs in about one in 2,500 live female births.

·  an ovum without any sex chromosome is fertilized by an X sperm, resulting in XO.

·  External genitalia look typical, but ovaries do not develop fully, causing amenorrhea and infertility.

·  Turner’s syndrome can cause short stature, immature breast development, abnormalities of certain internal organs, and mental retardation.

·  Administration of estrogen and progesterone can enhance the development of secondary sexual characteristics.

d. XYY syndrome and triple-X syndrome

·  occur rarely

·  may cause slight mental retardation and fertility problems.

2. Hormonal irregularities

a. A hermaphrodite is born with fully formed ovaries and fully formed testes, which is very, very rare.

b. Most individuals with intersex conditions are pseudohermaphrodites.

c. Adrenogenital syndrome (AGS)

·  A genetic female (XX) is exposed to large amounts of androgens during prenatal development.

·  The internal organs remain female, but the external organs may appear masculinized.

d. Androgen-insensitivity syndrome (AIS)

·  A genetic male (XY) does not respond to testosterone and develops internal testes with female external genitalia.

·  AIS is typically determined in adolescence when girls do not menstruate


·  gender roles—culturally defined behaviors seen as appropriate for males and females

·  gender traits—innate or biologically determined gender-specific behaviors

A. Girls Act Like Girls, Boys Act Like Boys

1. Masculinity and Femininity

a. Masculinity and femininity refer to the ideal cluster of traits that society attributes to each gender.

b. Most societies have cultural figures who are supposed to embody the traits of masculinity and femininity and serve as models for socializing youths into their gender roles.

c. Many studies have documented less gender role stereotyping in African American populations than in Caucasian populations.

d. Changing gender roles can result in confusion, fear, and even hostility in society because gender roles can allow for comfortable interaction between the sexes, since people can assume how they are supposed to behave in relation to the other sex.

B. Are Gender Roles Innate?

1. Behaviors are complex and are almost always interactions between one’s innate biological capacities and the environment in which one lives and acts.

2. Research has explored various physical traits, such as size, and emotional traits, such as mothering, to determine what traits might be innate, but no differences between the sexes are universally accepted by researchers.

C. Studying Gender

1. During the 1970s and 1980s, the focus of gender research was on girls, whereas increasing research is now being conducted on boys in addition to girls.

2. Researchers have also been interested in whether people overestimate or underestimate gender characteristics.


·  Socialization—the process whereby an infant is taught the basic skills for functioning in society

A. Evolutionary Biology: Adapting to Our Environment

B. Social Learning Theory

1. We learn our gender roles from our environment, and from the same system of rewards and punishments that we learn our other social roles.

2. Children learn to model their behavior after the same-gender parent to win parental approval.

3. Children also see models of the “appropriate” ways for their genders to behave in their books, on television, and when interacting with others.

C. Cognitive Development Theory: Age-State Learning

1. All children go through a universal pattern of development following the ideas of Piaget (1951), who suggested that social attitudes in children are mediated through their cognitive developmental level.

2. Children begin to categorize themselves based on the information they receive about their genders.

3. Rigid gender role behavior should decrease after the age of seven or eight, once children realize that gender roles are social and arbitrary.

D. Gender Schema Theory: Our Cultural Maps

1. According to Sandra Bem (1981; 1983; 1987), children think according to schemas, which are cognitive mechanisms that organize our world.

2. Gender schemas organize our thinking about gender as determined by culture.

3. The gender schema becomes so ingrained that people do not even realize that they are created by stereotypes.

E. Gender Hierarchy Theories: Power and Subordination

·  Men tend to be more frequently assigned to formal positions of power and authority in society, creating a gender hierarchy.

·  Theories have been developed to explain why societies value traits defined as male more than traits defined as female.

1. Chodorow’s Development Theory

a. Chodorow (1987) suggests that boys come to devalue the female role due to the separation process they must endure with their mothers.

b. To develop heterosexually, girls must separate from their mothers, which results in idealizing the qualities of their father the male role.

2. Ortner’s Culture/Nature Theory

a. Since culture, in the broad sense, sets human beings apart from animals, while childbirth and child-rearing are traits of all animals, men’s cultural roles are valued over women’s more biological roles.

b. Women are concerned with the “domestic domain” and men with the “public domain,” but since the public domain includes the domestic domain, women’s sphere of influence—the family—is subordinate to men’s.

3. MacKinnon’s Dominance Theory

a. “Male” and “female” are not biological categories but social and political categories.

b. Men define what is male and what is female, thus dominating social life.


·  Culture and social structure interact to create sex typing, a way of thinking that splits the world into two basic categories—male and female—and suggests that most behaviors, thoughts, actions, professions, emotions, and so on, fit one gender more than the other.

A. Masculinity

1. Williams & Best (1982) collected data about masculinity and femininity in thirty different countries and found that all had a general view of men as stronger, more active, and higher in achievement, autonomy, and aggression.

2. It is difficult for men to live up to the strong social demands of being male due to the contradictions inherent in masculinity.

3. Male stereotypes tend to be narrower than female stereotypes, and men who want to conform to society’s ideas of masculinity have less flexibility in their behavior than women who want to live up to feminine stereotypes.

B. Femininity

1. Sheila Rothman (1978) has argued that American society has gone through a number of basic conceptions of what “womanhood” should be, such as “virtuous” or “wife-companion.”

2. The messages women receive from modern North American culture are contradictory, such as messages about beauty and careers.

C. Androgyny: Feminine and Masculine

1. Androgyny refers to having both masculine and female characteristics.

2. In the 1970s, researchers suggested that androgyny was a desirable state, since androgynous individuals have greater flexibility in behavior because they have a greater repertoire of possible reactions to a situation.

D. Transgenderism

1. transgender—people who live full or part-time in the other gender’s role and derive psychosocial comfort in doing so.

2. transsexuals—a person who feels that he or she is trapped in the body of the wrong gender.

3. transvestite—a person who dresses in the clothing of the other gender and derives pleasure from doing so.

4. drag queens/female impersonators—professional actors, typically gay men, who dress in flamboyant women’s clothing to perform for a variety of reasons.

E. Transsexualism: When Gender and Biology Don’t Agree

1. A male transsexual feels that he is a female “trapped” in a man’s body; his gender identity is inconsistent with his or her biological sex which is called gender dysphoria.

2. Sex reassignment surgery (SRS) refers to the procedure where transsexuals have their bodies surgically altered to resemble those of the other sex.

3. More males than females report experiencing gender dysphoria.

4. Most transsexuals report a life-long desire to be a member of the other sex, which is typically satisfied only through sex reassignment surgery.

5. The process of seeking gender reassignment is long and complicated, involving a process of counseling, hormone therapy, and surgery.

F. Third Genders: Other Cultures, Other Options

1. Some cultures have a gender category that is neither male nor female—a third gender.

2. A category of individuals in many Native American societies called a berdache was usually a biological male who was effeminate or androgynous in behavior and who took on the social role of females.

3. Third gender categories with varying roles and positions in society have existed in a variety of cultures including Oman, India, Thailand, Hawaii, and Tahiti.

G.  Asexualism

·  An individual born either XX or XY but without internal or external sexual organs.


·  gender-identity disorder—diagnosis given to children who have a strong and persistent identification with the other sex or the gender role of the other sex and may be uncomfortable with their own biological sex or gender role.

A. Childhood: Learning by Playing

1. As early as age two, modeling behavior begins to emerge, and children begin to realize that objects and activities are appropriate to specific genders, and they believe that these gender rules are fixed rather than flexible.

2. Early in childhood, gender segregation or homosocial play begins, which may be due to different playing styles, attraction to similarities, or learned social roles.

3. During the school years, children become judged by peers and teachers based on gender roles, with boys experiencing more rejection from peers for violating gender stereotypes.

B. Adolescence: Practice Being Female or Male

1. By adolescence, gender roles are firmly established, and they guide adolescents through their exploration of peer and romantic relationships.

2. Gender role expectations can be challenging in adolescence for gay, lesbian, bisexual, and transgender adolescents.

3. Gender roles in adolescence are changing, particularly in regards to heterosexual relationships.

C. Adulthood: Careers and Families

1. Gender socialization pressures shape career choices for women and men.

2. In recent years, men’s and women’s roles have been changing in the workplace.

3. Women and family life