role of chromosmes and hormones

• How many chromosomes are there in the human body?

  46 ( 23 pairs )
• Which chromosome determines sex?

  the last pair (23rd)
• what is the chromosomal structure of females?

  XX
• What is the chromosomal structure of males?

  XY
• what is significant about the Y chromosome?

  Carries a gene called SRY which causes the development of the embryo

  • this then produced androgens developing the embryo into a male
• testosterone

  Male hormone controls the development of the male sex organs.

  • links to aggression
  • female rats that get injected with testosterone become more aggressive
• Oestrogen

  Female hormone that determines female characteristics and menstruation

  • Can cause women to experience heightened emotionality and irritability during their menstrual cycle - PMS
• Oxytocin

  women produce oxytocin in much larger amounts than men, particularly as a result of giving birth

  • stimulates lactation
  • reduces the stress hormone cortisol and facilitates bonding
• Oversimplifies a complex concept

  Reducing gender to the level of chromosomes and hormones has been accused of ignoring alternative explanations of gender development.

  • The cognitive approach would draw attention to the changing thought process that underpins gender development
• evidence support

  David Reimer

  • in a prison population, those with the highest level of testosterone were more likely to have commented on violent or sexually motivated crimes

  Transgender women showed a decrease in the aggression and visual spatial skills whist transgender men showed the opposite
• contradictory evidence

  in a double bind study where 43 males were given a weekly testosterone injection or a placebo. No significant differences in aggression were found after the 10 weeks.