the role of chromosomes and hormones Flashcards
how many pairs of chromosomes do we have
23
what is the role of the Y chromosome in males
-determines an individual’s sex
-causes changes to the embryo from a very early age
-carries little genetic information
what is the SRY gene
the Y chromosome carries the ‘sex-determining region Y’, or STY
what does the SRY gene do
-caused the testes to develop
-testes then produce androgens (male sex hormone)
-these androgens cause the embryo to become a male (without them it develops into a female)
what’re hormones functions
-most gender development comes from hormones
-in the womb hormones act upon brain development and cause the development of the reproductive organs
-in puberty hormonal activity triggers the development of secondary sexual characteristics such as pubic hair
what is the function of testosterone
-male hormone that controls the development of male sex organs, that begin to be produced at ~8 weeks of foetal development
-human/animal studies are used to show the effects of increased testosterone: Nanne Van de Poll et al. showed female rats injected with testosterone to have been more physically/sexually aggressive
what did Wang do
showed the link between testosterone and sexual behaviour, studying males with hypogonadism, Wang gave 227 hypogonadal men testosterone therapy for 180 days
what did Wang find
testosterone replacement improved sexual function, libido and mood, and significantly increased muscle strength in the sample
what is the function of oestrogen
-female hormone that determines female sexual characteristics and menstruation
-as well as physicality, oestrogen causes some to experience heightened emotionality and irritability during their menstrual cycle
-this is PMT of PMS when they become a diagnosable disorder
-some dispute PMS as a viable medical category
what’s the function of oxytocin
-women produce oxytocin in much larger amounts than men
-causes contraction of the uterus during labour, stimulate lactation, reduce cortisol and facilitates bonding
-AKA ‘love hormone’ it makes new mothers feel ‘in love’ with their baby
-men producing far less than women fuels the stereotype of men being less interested in closeness in a relationship, however men produce more oxytocin when performing sexual activities/kissing
what was the case of David Reiner
-Bruce lost his penis and testes in a failed cauterised circumcision
-John Money worked with his parents believing ‘gender’ to be more nurture-influenced than nature
-John Money was wrong and Brenda (formerly bruce) was very uncomfortable as a girl and was relieved to be told of being born a male and adopted the name ‘David’
-David later committed suicide
-shows support for the influence of nature (chromosomes)
what’re 3 negative evaluation points of the role of chromosomes and hormones in determining gender
PMS
O’Connor’s double blind testosterone study
Overemphasis on nature
how is PMS a negative eval of hormones in determining gender
some see PMS as a social construct, not a biological fact, which encourages damaging stereotypes of ‘irrational women’ affecting how women are treated.
suggests that the benefits of treatment may not be justified because enhancing negative expectations about women may, eg, damage their workplace equal rights
how is O’Connors double blind testosterone study a negative eval on the role of chromosomes and hormones in determining gender
-double-blind study on 43 males, a weekly injection consisted of either testosterone or a placebo
-found no significant differences in aggression levels, frequency of sexual intercourse, or sex-drive levels
-suggests that additional testosterone has no effect on ‘normal’ adults, though doesn’t challenge testosterone’s importance in early development
how is the overemphasis on nature a negative eval for the role of chromosomes and hormones in determining gender and roles
Hofstede et al claim that gender roles are more a consequence of social norms rather than biology, eg individualistic countries are more masculine in their outlook and value masculine traits.
this challenges the biological explanation and suggests that social factors may be more important in shaping gender behaviour and attitude
