role of chromosomes and hormones

• role of chromosomes

  found in the nucleus of living cells carrying information in the form of genes

  46 chromosomes in body arranged into 23 pairs, with the last pair determining biological sex
• role of chromosomes

  chromosomal structure for female - XX, for men - XY

  baby’s sex determined by the sperm that fertilises the egg cell

  fertilising sperm has X chromosome = will be girl

  fertilising sperm has Y chromosome = will be boy
• role of chromosomes

  Y chromosome carries a sex determining region Y (SRY) which causes testes to develop in an XY embryo which produce androgens -male sex hormones

  without androgens, embryo develops into a female
• hormones

  a chemical substance circulated in the blood that controls and regulates the activity of certain cells or organs
• role of hormones

  gender development come through influence of hormones

  in womb , hormones acts upon brain development and cause development of the reproductive organs

  in puberty, a burst of hormonal activity triggers the development of secondary sexual characteristics
• testosterone

  male hormone which controls the development of male sex organs

  associated with aggressiveness
• role of testosterone

  van de poll et al showed that female rats who had been injected with testosterone had become more physically and sexually aggressive
• congenital adrenal hyperplasia (CAH) is a rare genetic disorder that causes high prenatal levels of testosterone


  is easily identified in newborn baby girls who may have ambiguous genitals due to the masculinising effects of the male hormones
• berenbaum and bailey found females with CAH are often described by the family and friends as tomboys, exhibit higher levels of aggression than other girls and show a preference for male toys
• oestrogen

  female hormone that determines female sexual characteristics and menstruation
• role of oestrogen

  causes heightened emotionality and irritability in menstrual cycle - pre menstrual syndrome (PMS)

  pms used as a defence in cases of shoplifting and even murder
• X overemphasis on nature - if gender identity is purely based on biology, then we should expect to find more differences in male and female behaviour than there actually are
• X maccoby and jacklin - found significantly more differences in behaviour within the sexes than between them - overemphasising nature
• X social learning theory - importance of social context in the meaning of our gender identity and gender role

  • influence of social norms explains cross cultural differences in gender role behaviour
• X cognitive approach would use the changing though processes that underpin gender development

  • even though these may come from the maturation of the developing brain, it’s not full explained by the biological model
• X although the biological approach acknowledges the importance of innate factors in gender development, the psychodynamic approach points to the importance of childhood experiences eg. interactions within family
• X biological accounts that reduce gender to the level of chromosomes have been accused of ignoring alternative explanations for gender development
• ✔️ van goozen et al - studied transgender individuals who were undergoing hormone treatment and were being injected with hormones of the opposite sex 


  transgender women showed decreases in aggression and visuo spatial skills

  transgender men showed an increase

  suggests that sex hormones do exert some influence in gender related behaviours
• ✔️dabbs et al - in a prison population, offenders with the highest levels of testosterone were more likely to have committed violent or sexually motivated crimes
• X tricker et al - double bind study

  43 males given either a weekly injunction of testosterone or a placebo

  • no significant differences in aggression were found after the 10 week period between the 2 groups
• X goozen study involved small samples of unusual people - limits the extent of making generalisations
• X some studies of biological factors in gender are conducted in animals - reduces generalisability
• X effects of oestrogen levels in a woman’s moods stereotypes female emotion and experience
• X rodin - PMS is a social construct, not a biological fact but a way of privileging men over women