chromosomes and hormones

• testes development

  • gene on Y chromosome
  • produce androgens
  • triggers sex differences in Brain and primary and secondary sex characteristics
• chromosomes

  observable variations

  neuronal structures SDN 2.5 bigger in genetic males

  professor Swaab
• hormones

  testosterone - 10 times more in M - secondary sex characteristics - linked to aggression (masculine traits)

  oestrogen - female - regulate menstrual cycle and secondary sex characteristics - maternal behaviours (high after birth) low levels = irritability

  oxytocin - more females - higher lactation and reduces eddects of stress Cortisol - caring attachment behaviour
• SRY 


  develop testes and stop ovaries
• A03 young

  1966

  manipulated exposure level testosterone to unborn baby rats

  females borm masculinised with masculine traits

  played aggressively and more exploratory behaviour

  increased SDN size in comparison to female controls

  evidence for hormones influencing brain structure and biology causing gendered behaviour
• A03 use of animal research

  • useful as lack of confounding variables - socialisation change gendered behaviour
  • however difficulties extrapolating
  • differences in brains - humans more advance and evolved as can identify thoughts and feelings have more awareness
  • gender construct and can express gendered behaviours where interpreted in animals
  • difficult to conclude wether gender is being measured - lack of internal validity
• A03 money

  • theory of neutrality
  • carried out case study of bruce reimer however findings contradict money's theory that behaviour is learned through socialisation
  • Genetic male reassigned as a baby and raised as a girl with hormone but felt isolated and as if boy so reversed surgery
  • biologically gender is assigned - not based on social learning theory
  • brain structures and genetics are responsible.
• A03 reductionist

  complex process of gender development has been simplified to the role of genetics and hormones ignoring the complexity of biology and individuals present

  hormone levels are not fixed and fluctuate

  Van anders

  • testosterone levels increase in women when role-play tasks wielding power over another
  • can't identify cause and effect
  • perhaps testosterone levels higher in males as a result of gendered behaviour rather than the cause as society encourages men to be more competitive and hbae greater power

  socially sensitive as a result