Chromosomes & Hormones

Question 1

What chromosomes do girls have?

Answer 1

XX

Question 2

What chromosomes do boys have?

Answer 2

XY

Question 3

What happens in the first 6 to 8 weeks after conception?

Answer 3

Male and female embryos are identical, and have the capacity to generate either a male reproductive system or a female reproductive system

Question 4

What happens around 8 weeks after conception?

Answer 4

The gene on the 23rd chromosome instructs the glands in the embryo to release hormones

Question 5

What happens in the male XY embryo?

Answer 5

Male hormones called androgens, in this case testosterone, stimulate the development of the male reproductive system and suppress the development of the female reproduct ive system leading to the development of testes and penis

Question 6

What happens in the female XX embryo?

Answer 6

Hardly any secretion of hormone takes place, meaning that the ‘default’ female reproductive system develops with ovaries and a vagina

Question 7

What is testosterone associated with?

Answer 7

The masculinisation of the brain and types of behaviours such as competitveness and aggressiveness

Question 8

What did Quadagno et al find?

Answer 8

That female monkeys who were deliberately exposed to testosterone during parental development later engaged in more rough and tumble play than other females and were more aggressive

Question 9

What did Hines do?

Answer 9

Studied female babies born to mothers who had been given injections of male hormones during pregnancy to prevent miscarriage

Question 10

What did Hines find?

Answer 10

The babies were more aggressive than normal female children and Hines concluded the extra testosterone in the womb had affected later behaviour

Question 11

What did Swaab and Fliers do?

Answer 11

Analysed 13 makes and 18 females ages 10-93 and found that the volume of the exhale dismorphic nucleus was 2.5 times larger in males, this area is partly responsible for sexual behaviour

Question 12

What did Imperato-McGinley et al do?

Answer 12

Studied a family in the Dominican Republic, 4/10 children in the Barista family have changed form being born and growing up as girls into men

Question 13

What happened to these children?

Answer 13

They were brown with normal female genitalia and when they were 12, their vaginas healed over, then 2 testicles descended and they grew full size penises

Question 14

What did Money do?

Answer 14

The case study of David Reimer, identical twin boys were raised normally until at 8 months one of them suffered removal of his penis when a circumcision went wrong

Question 15

What did David’s parents do?

Answer 15

After consulting with Dr Money they decided to raise him as a girl, at 22 months Brenda was surgically castrated, given oestrogen and a vaginal canal was constructed

Question 16

What happened when Brenda reached her teens?

Answer 16

She was unhappy and uncertain about her gender identity, at 12 she reluctantly began taking oestrogen and soon developed, but she resisted further vaginal surgery

Question 17

What happened when she become 14?

Answer 17

The female hormones were now competing with her male hormonal system, she changed her name to David and underwent sex reassignment surgery

Question 18

What were the conclusions of David Reimer’s case study?

Answer 18

Although he had been raised as a girl the male hormones were too powerful

Question 19

What does oestrogen do?

Answer 19

Promotes the development and maintenance of female characteristics of the body and is seen later to regulate menstruation

Question 20

What does oestrogen do to the body?

Answer 20

• Development of breast
• Premenstrual tension

Question 21

What does oestrogen play a role on?

Answer 21

Feminising the brain, oestrogen promotes neural interconnections for a more ‘distributed’ female brain

Question 22

What is oestrogen associated with?

Answer 22

Female-type behaviours such as sensitivity and cooperation

Question 23

What did Albrecht and Pepe find?

Answer 23

That increasing oestrogen levels in pregnant baboons led to heightened cortisol production, which assisted the development of organs and tissues in foetuses and led to reduced levels of miscarriage by regulating progesterone levels

Question 24

What is oxytocin?

Answer 24

A hormone that acts as a neurotransmitter and is produced in both female and males to control key aspects of the reproductive system

Question 25

What does oxytocin help?

Answer 25

Facilitate childbirth by helping to stimulate contractions and reduces the stress hormone cortisol to facilitate bonding

Question 26

How does oxytocin affect female social behaviour?

Answer 26

Mate selection, bestibg behaviour, monogamy and pair bonding as well as nurturing, acceptance and protection of offspring

Question 27

What did White-Traut et al do?

Answer 27

Measured oxytocin levels in saliva produced by females before, during and after breastfeeding

Question 28

What did White-Traut find?

Answer 28

levels were highest immediately before feeding, decreased at initiation of feeding and rose again 30 minutes after feeding, illustrating oxytocin’s important role in promoting breastfeeding

Question 29

What is an evaluation of Quadagno’s study?

Answer 29

The methodology is problematic as we cannot generalise to humans as animals have different DNA, habitats and lifestyles

Question 30

What is an evaluation of Hine’s study?

Answer 30

It is more generalisable and valid as human participants are used

Question 31

What are 3 evaluations of David Reimer?

Answer 31

• High ecological validity
• Cannot be generalised
• High qualitative data

Question 32

What are some evaluations of the Barista boys?

Answer 32

Culture bias as it only focuses on one culture so it cannot be generalised