A2 GENDER - EFFECT OF CHROMOSOMES AND HORMONES ON GENDER

Question 1

Describe typical chromosome patterns in males and females

Answer 1

We have 23 pairs of chromosomes, the 23rd pair determines the gender. As the egg always gives an X chromosome, the father determines the sex of the baby, as the sperm can donate an X or a Y.

The Y chromosome contains the SRY (Sex determining Region Y) gene, which releases a surge of the male sex hormones (androgens) at 8 weeks to form testicles and then again at puberty for changes e.g. facial and pubic hair

Question 2

Evaluate testosterone on gender development

Answer 2

(+) Barenbaum and Bailey (2003) studied females w/ CAH (Congentital Adrenal Hyperplasia), which causes abnormally high levels of testosterone; found they preferred “boys’ toys” and were more aggressive; typically masculine characteristics so gender could be influenced by hormones
(+) Quadagno (1977) injected female monkeys w/ testosterone and found they were more aggressive; hormones affect beh
(-) We can’t necessarily generalise findings from monkeys to humans, and the ppts w/ CAH may have had other extraneous variables so the findings may only apply to females w/ CAH
(-) Research shows that females who think they are being given testosterone tend to behave more aggressively than females who know they’re being given a placebo; shows we do have quite a lot of choice over our own beh so gender can’t just be due to hormones

Question 3

Describe and evaluate oestrogen

Answer 3

Oestrogen is used in the dev of female sex organs and is also responsible for menstruation and linked to heightened emotions and irritability

(-) Rodin (1992) criticises the idea of PMS and argues that the effects of oestrogen don’t really exist and that it’s a social construction that privileges men to make women seem weak and “medicalise” their emotions

Question 4

Describe oxytocin

Answer 4

• Responsible for stimulating contractions to give birth and for activating lactation after birth
• Reduces stress hormones to allow bonding after birth
• Produced more in women but men do have oxytocin

Question 5

Evaluate effects of hormones on gender dev as a whole

Answer 5

(+) Barenbaum and Bailey (2003) studied females w/ CAH (Congentital Adrenal Hyperplasia), which causes abnormally high levels of testosterone; found they preferred “boys’ toys” and were more aggressive; typically masculine characteristics so gender could be influenced by hormones
(+) Quadagno (1977) injected female monkeys w/ testosterone and found they were more aggressive; hormones affect beh
(-) We can’t necessarily generalise findings from monkeys to humans, and the ppts w/ CAH may have had other extraneous variables so the findings may only apply to females w/ CAH
(-) Research shows that females who think they are being given testosterone tend to behave more aggressively than females who know they’re being given a placebo; shows we do have quite a lot of choice over our own beh so gender can’t just be due to hormones
(+) David Reimer case study; born Bruce, genitals destroyed in failed circumcision, raised as Brenda, around teenage years hormones took over and Brenda became “deeply troubled”, eventually became David
(-) Rodin (1992) criticises the idea of PMS and argues that the effects of oestrogen don’t really exist and that it’s a social construction that privileges men to make women seem weak and “medicalise” their emotions

Question 6

Describe Klinefelter’s syndrome as an atypical sex chromosome pattern

Answer 6

Affects 1 in every 500-1000 males and is caused by an XXY chromosome pattern.

Physical symptoms: enlarged/excess breast tissue, small genitals, growing taller than expected, large hips and long legs, more susceptible to breast cancer

Psychological symptoms: Shyness, links to anxiety/depression, difficulty socialising and expressing emotions, problems with cog functioning and problem solving

Question 7

Describe Turner’s syndrome as an atypical sex chromosome pattern

Answer 7

Affects 1 in every 5000 females (think Tina Turner) and is caused by an X (or XO) chromosome pattern

Physical symptoms: underdev.ed ovaries, shorter than normal, thick webbed neck, no normal menstrual cycle, low set ears

Psychological symptoms: difficulties understanding social relationships, hard to keep friendships, very good reading ability, low maths and visuo-spatial ability

Question 8

Evaluate atypical sex chromosome patterns

Answer 8

(+) Contributes to the wider nature/nurture debate; nature influences their gender
(-) However, people w/ Klinefelter’s or Turner’s syndrome may be treated differently as a result so may be a bigger influence from nurture than originally thought
(-) Unusual sample of people and low generalisability
(+) Increased awareness and research leads to earlier diagnosis and better treatment; Herlihy et al (2011) found those diagnosed w/ K’s or T’s syndrome early on had sig benefits over those diagnosed in adulthood