Genes: Our Biological Blueprint

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1 Nature--Nurture

2 Genes: Our Biological Blueprint Chromosomes threadlike structures made of DNA that contain the genes DNA (deoxyribonucleic acid) complex molecule containing the genetic information that makes up the chromosomes has two strands-forming a double helix --held together by bonds between pairs of nucleotides

3 Genes: Our Biological Blueprint Genes biochemical units of heredity that make up the chromosomes a segment of DNA capable of synthesizing a protein Genome the complete instructions for making an organism consisting of all the genetic material in its chromosomes

4 Genes: Our Biological Blueprint Nucleotide ATCG part of an alphabet that consists of only four letters; the sequence is nearly identical in all humans. Nucleotides

5 Overview of Genetics Humans have 23 pairs of chromosomes Chromosomes are long twisted strands of DNA DNA is the chemical basis of heredity and carries instructions Genes are the basic unit of heredity; single unit of DNA on the chromosome Normal Female Karyotype

6 enes: Their Location and Composition

7 Genes: Dominant and Recessive Genotype underlying genetic makeup, what category do you fit in? Phenotype traits that are expressed Dominant genes will always be expressed if present Recessive genes will not be expressed unless they are in a pair

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9 Can You Do This With Your Tongue? Dominant trait. R.

10 Sex Linked Traits Traits linked to the X or Y (sex) chromosomes Usually recessive and carried on the X chromosome Appear more frequently in one sex than another Color blindness, baldness, hemophilia, Fragile X

11 Identical or Fraternal

12 Environmental Influence Two placental arrangements in identical twins

13 Twin and Adoption Studies Studying the effects of heredity and environment on two sets of twins, identical and fraternal.

14 Twin Studies Separated identical twins Fraternal twins Why can these be useful?

15 Separated Twins Studies have compared identical twins who are reared separately from birth, and have found numerous similarities including...

16 Do only twins have things in common? Find people in the room that share things in common with you. Birthday- Height shoe size favorite color favorite type of movie music job goals sports hobbies favorite subject foods cars sleeping habits books gum toothpaste cell phone magazines pets - unusual talents- habits vacation spots social preferences dating status handedness major illnesses.

17 Adoptive v. Biological Relatives Support for twin studies has been strengthened by Adoptive Studies. Adopted children (biologically unrelated) tend to share significantly less with their adopted family than do children of biological families.

18 Adoptive Studies Adoptive studies strongly point to the simple fact that biologically related children turn out to be different in a family. Do siblings have differing experiences? So? Do siblings, despite sharing half of their genes, have different combinations of the other half of their genes? Ultimate question: Does parenting have an effect?

19 Parenting Parenting does have an effect on biologically related AND unrelated children.

20 Temperament and Heredity Temperament refers to a person s stable emotional reactivity and intensity. Identical twins express similar temperaments, suggesting that heredity predisposes temperament. How is your temperament compared to your siblings? Parents?

21 Heritability Herit- part of inherit. Which means to posses something that someone has given you. We inherit our traits and qualities from our parents. -ability- as a suffix means capable. If a trait is passed from one generation to the next, then it is capable of showing up in the children of people who possess that quality. A heritable trait is one that can be passed down from parent to child. 21

22 Gene-Environment Interaction Genes can influence traits which affect responses, and environment can affect gene activity. For Example A genetic predisposition that makes a child restless and hyperactive evokes an angry response from his parents. A stressful environment can trigger genes to manufacture neurotransmitters leading to depression.

23 Gene-Environment Interaction Due to a genetic predisposition to be attractive, sociable, and easygoing, one baby may receive more affectionate care leading the baby to develop into a more outgoing or perhaps compassionate adult.

24 Gene-Environment Interaction Try this one. Why doesn t the attractive guy/girl have any common sense? Is this a common misconception?

25 Molecular Genetics Identifying specific genes influencing behavior. Should we pre-screen our fetuses? China and India check for gender, how has that worked out?

26 Evolutionary Psychology Natural Selection the principle that, among the range of inherited trait variations, those that lead to increased reproduction and survival will most likely be passed on to succeeding generations Mutations random errors in gene replication that lead to a change in the sequence of nucleotides the source of all genetic diversity

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28 Evolutionary Psychology Evolutionary Psychology the study of the evolution of behavior and the mind, using the principles of natural selection Gender in psychology, the characteristics, whether biologically or socially influenced, by which people define male and female

29 * Evolutionary Psychology In Choosing A Mate- Men preferred attractive physical features suggesting youth and health Women preferred wealth and social status

30 Evolutionary Psychology Critiquing the Evolutionary Explanation Evolutionary psychologists make too many hindsight explanations.

31 Behavior Genetics Behavior Genetics study of the relative power and limits of genetic and environmental influences on behavior Environment every nongenetic influence, from prenatal nutrition to the people and things around us

32 Behavior Genetics Temperament a person s characteristic emotional reactivity and intensity Heritability the proportion of variation among individuals that we can attribute to genes may vary, depending on the range of populations and environments studied

33 Behavior Genetics Interaction the dependence of the effect of one factor (such as environment) on another factor (such as heredity) Molecular Genetics the subfield of biology that studies the molecular structure and function of genes

34 Environmental Influence Culture the enduring behaviors, ideas, attitudes, and traditions shared by a large group of people and transmitted from one generation to the next Norm an understood rule for accepted and expected behavior

35 Environmental Influence Personal Space the buffer zone we like to maintain around our bodies Memes self-replicating ideas, fashions, and innovations passed from person to person

36 The Nature and Nurture of Gender X Chromosome--the sex chromosome found in both men and women females have two; males have one an X chromosome from each parent produces a female child Y Chromosome--the sex chromosome found only in men when paired with an X chromosome from the mother, it produces a male child

37 The Nature and Nurture of Gender Testosterone * the most important of the male sex hormones * both males and females have it * additional testosterone in males stimulates growth of male sex organs in the fetus development of male sex characteristics during puberty Role * a set of expectations (norms) about a social position * defining how those in the position ought to behave

38 The Nature and Nurture of Gender Gender Role a set of expected behaviors for males and females Gender Identity one s sense of being male or female Gender-typing the acquisition of a traditional masculine or feminine role

39 Gender Role Stereotypes The beliefs and expectations people hold about the typical characteristics, preferences, and behaviors of men and women In the US, men and women view the female stereotype more positively than the male stereotype. This is called benevolent sexism There is a high degree of agreement on the characteristics associated with each sex among people of many different cultures

40 Gender Related Differences Differences do not mean deficiencies Three main areas of gender differences Personality Cognitive abilities Sexual attitudes and behaviors

41 Personality Differences No significant differences between men and women on most characteristics Women tend to be more nurturant than men Men tend to be more assertive than women

42 Cognitive Differences No differences for most cognitive abilities Verbal, reading, and writing females consistently score higher Spatial skills males outscore females on mentally rotating objects, females score better on remembering locations of objects Math Skills males score slightly better than females

43 Sexual Attitudes and Behaviors Reported differences between males and females in these areas have become less pronounced since the 1960s Recent meta-analyses indicate that men tend to have more sexual partners, experience first intercourse at an earlier age, and masturbate more frequently than women.

44 Gender Role Development Between ages 2-3 years, children can identify themselves and other children as boys or girls. The concept of gender or sex, however is based more on outward characteristics such as clothing. Toddler girls tend to play more with dolls and ask for help more than boys Toddler boys tend to play more with trucks and wagons, and tend to play more actively After age 3 years we see consistent gender differences in preferred toys and activities

45 The Nature and Nurture of Gender Gender and Culture

46 The Nature and Nurture of Gender

47 The Nature and Nurture of Gender Social Learning Theory theory that we learn social behavior by observing and imitating and by being rewarded or punished Gender Schema Theory theory that children learn from their cultures a concept of what it means to be male and female and that they adjust their behavior accordingly

48 The Nature and Nurture of Gender Two theories of gender typing

49 Gender Concepts Gender Gender Identity Gender Stereotypes Click a button for more information. Originally, gender referred to what society viewed as appropriate for males and females. Now, gender can refer to the sex of the person. Gender Roles

50 Gender Concepts Gender Click a button for more information. Gender Identity A person s perception of being male or female Gender Stereotypes Gender Roles

51 Gender Concepts Gender Click a button for more information. Gender Identity Gender Stereotypes Widely-held, often inaccurate beliefs about ability and personality traits based on sex Gender Roles

52 Gender Concepts Gender Click a button for more information. Gender Identity Gender Stereotypes Gender Roles Culturally-defined roles for males and females

53 The Role of Hormones Hormones are chemicals that control bodily responses such as emotions, growth, and sexuality. The sex hormones are estrogen and androgen. 4 Males have more androgen. 4 Females have more estrogen. 4 Hormones play a lesser role in human development and behavior than they do in animals.

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55 Male/Female Differences The only activity that is clearly defined along gender lines is reproduction. All other activities are shared by both sexes to different degrees. Nurturance: Women generally show more empathy, but males can also be nurturing. No one has proven the existence of strong maternal instinct in humans.

56 Aggression: Males are aggressive in more situations than females. Females do show aggression in some situations, however. Physical activity: Boys start out more physically active. By adulthood, differences in activity levels between genders have disappeared.

57 Intelligence Males and females are very close in overall intellectual abilities. Spatial Skills Skills involving the ability to imagine how objects would look when moved about in space. Males generally do better though social role, social class, ethnic background, and the type of test given also play roles.

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60 Mathematical Ability Studies are not clear and have not as yet conclusively shown that males are innately better at math Males do better than females on the SAT math section, but study findings have not been consistent. 4 Teachers and parents have higher expectations for males. 4 Females may avoid difficult areas such as math. 368 x 42

61 Verbal Ability Includes not just speaking but also word problems, reading and writing. Generally, girls do better than males until early adolescence.

62 Social Factors Self-Confidence 4 In adolescence, females confidence often declines (concerned with #1 how boys will react to them?). 4 The loss of confidence is highest in whites and Hispanics and lowest in African Americans. 4 Overall, studies have not found major differences in self-confidence levels between males and females.

63 Friendships 4 Boys groups usually have a leader, girls have more equal status in groups. 4 Boys usually issue orders and demands while girls make more suggestions. 4 Adult females tend to have a best friend of the same sex while males do not. 4 Adult females have a few close friends while males have a larger number of male acquaintances. 4 Females initiate most breakups.

64 Communication Men Women 4 Talk more and interrupt more 4Touch more 4Disclose less about self 4 Boys sit next to one another 4 Males offer solutions to problems 4 Talk less and interrupt less 4 Are the ones being touched 4 Disclose more about themselves 4 Girls sit facing one another 4 Girls share similar stories

65 Selecting a Mate Overall, the top eight characteristics for potential mate selection are: 1. Social Status 2. Economic Status 3. Physical Attractiveness 4. Personality 5. Intelligence 6. Ambition 7. Character 8. Sense of Humor

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67 Gender Role Behavior Gender role behaviors reflect what society says are appropriate actions for males and females. Through identification with a parent of the same sex, people learn how to behave appropriately. Which jobs are appropriate for males? for females?

68 Gender studies have shown 4 Fathers who are very warm toward daughters tend to produce mild tomboyishness in girls. 4 Boys whose fathers were absent during preschool years tend to be less aggressive and not as active in sports. 4 People who are considered mentally healthy tend not to have excessive masculine or feminine qualities. 4 Children tend to identify with the dominant parent in the household, even across sex lines.

69 4 Fathers are more determined that appropriate activities are given to young male children. 4 People handle babies differently depending on whether they are identified as male or female. 4 People will assign different characteristics to babies when they are identified as male or female.

70 Mixing Gender Roles Rigid extremes for gender roles for males and females restrict the full range of human behaviors and emotions. Androgynous people are high in male and female characteristics. Androgynous behavior can lead to more flexibility and willingness to share characteristics of members of the opposite sex.

71 Gender-Busting Communication Hints (for Males) 1. Do you frequently interrupt females while they are speaking? Try to break the habit. 2. Avoid answering questions with Nope and Yep. Try to explain more and give some details why you did something. 3. Try to open up on personal issues. 4. Ask for help if you need it. Can you tell me how to get to...?

72 Gender-Busting Communication Hints (for Females) 1. Look people directly in the eye. 2. If men interrupt conversations, assertively direct the conversation back. 3. Do not over-apologize for your behaviors. 4. Talk more often about current events, less about people.