The role of chromosomes and hormones Flashcards
What are chromosomes?
Found in the nucleus of cells carrying all the genetic information (DNA) for an organism – there are 46 in the nucleus (23 pairs)
What are hormones?
Chemical messengers circulated in the blood that control and regulate the activity of certain cells and organs
What is the main male-dominant hormone?
Testosterone
What are the main female-dominant hormones?
- Oestrogen
- Oxytocin
What is testosterone?
Affects the development of male sex organs prenatally and male secondary sexual characteristics during puberty
What is oestrogen?
Affects the development of females sex organs prenatally and female secondary sexual characteristics during puberty and directs the menstrual cycle
What is oxytocin?
Promotes feelings of bonding in men and women; stimulates lactation allowing mothers to breastfeed their children
What is a case study which supports the biological explanation for gender?
David Reimer
What is a case study for the biological explanations for gender?
Case study of David Reimer:
David started life as Bruce Reimer and had an identical twin, Brian. When the twins were 6 months old, they were circumcised to cure a urinary problem. Tragically, the operation on Bruce was botched and Bruce’s penis was all but burned off. Bruce’s parents sought advice from Dr. Money, who said that Bruce should have his penis and testes removed so he looked like a girl and he should be raised as Brenda.
Over the next 10 years the twins, now Brian and Brenda, visited Money regularly because the case provided a unique natural experiment, a normal XY male raised as a female with an identical twin brother as a control. Money regularly reported on the twins, claiming that the gender assignment had been a success and advising that this was the way forward for intersex individuals.
However, it turned out that David was by no means happy and, when he was told his true sex in his teen years, he decided to change and live as a man, taking on the name David. He was quoted saying, ‘suddenly it all made sense why I felt the way I did. I wasn’t some sort of weirdo.’ Unfortunately, he never recovered from the events of his early life and committed suicide in 2004.
What are the two strengths for the role of chromosomes and hormones?
Research support for biological determinism- The case study of David Reimer showed that despite being raised as a girl, David showed a strong male identity.
Reiner and Gearhart (2004) studied 16 genetic males born with almost no penis. Two were raised as males and remained males; the remaining 14 were raised as females. 8 of these females reassigned themselves as males by the age of 16.
Counter-argument- Imperato-McGinley et al. (1974) studied the Batista family from the Dominican Republic. 4 children born with external female genitalia and raised as girls. When they hit puberty the large amounts of testosterone caused their male genitalia to appear externally. These children were genetically XY, but their male genitalia had not appeared at birth because of an inherited gene that caused testosterone insensitivity. The ‘girls’ accepted their new male role without any difficulty. This suggests that cultural and social influences played a role here. The ease of transition from female to male was due to the acceptance of fluidity in gender roles in this community, which is not so accepted in Western cultures. This case suggests that culture can shape gender development.
Support for the effect of hormones- Quadagno et al. (1977) found that female monkeys who were deliberately exposed to testosterone during prenatal development later engaged in more rough-and-tumble play than other females and were more aggressive.
Counter-argument: there are issues generalising from non-human animal studies because human behaviour is governed by expectations and deliberate choice.
What are the two limitations for the role of chromosomes and hormones?
Reductionist view- Reduces the concept of gender to a chromosomal and hormonal level —> ignores alternative explanations for gender development.
The cognitive approach would draw attention to the changing thought processes that underpin gender development. Even though these may come about through maturation of the developing brain, they are not adequately explained by the biological model.
Social learning theory would highlight that the social context is important in the learning of gender identity and gender role. The influence of social norms would explain cross-cultural differences in gender-role behaviour (e.g. Batista family).
Overemphasis on nature- If gender identity is purely down to nature (biology) then we would expect to find more differences in male and female behaviour than there actually are.
Maccoby and Jacklin (1974) found significantly more differences in behaviour within the sexes than between them.
