Gender - Role Of Chromosomes + Hormones Flashcards
(28 cards)
What are chromosomes?
Chromosomes are 46 thread-like structures (23 pairs) made of DNA inside the nucleus of each cell. They carry genetic information (genotypes) that influence physical and behavioural characteristics (phenotypes).
What determines biological sex?
The 23rd pair of chromosomes determines biological sex — XX = female, XY = male.
What is the role of the Y chromosome?
The Y chromosome contains the SRY gene, which triggers the development of testes.
What do testes produce?
Testes produce androgens (male sex hormones), which develop male physical traits.
How do genetic differences influence gender expression?
Genetic differences between biological males and females may lead to observable behavioural variations due to different neuronal structures and hormone levels.
What are hormones?
Hormones are biochemical messengers released into the bloodstream that influence organs and behaviour.
What is testosterone?
Testosterone is an androgen (male sex hormone), produced 10x more in males than females.
What is the role of testosterone in sex?
Testosterone influences foetal development of testes and secondary sexual characteristics (e.g. facial hair, muscle growth).
What is the role of testosterone in gender?
Testosterone is associated with aggression and dominant behaviour.
What is oestrogen?
Oestrogen is the primary female sex hormone, found in much higher levels in females.
What is the role of oestrogen in sex?
Oestrogen regulates the menstrual cycle and development of secondary sex traits.
What is the role of oestrogen in gender?
Oestrogen is linked to maternal caregiving after birth and emotional sensitivity, e.g. mood swings due to oestrogen fluctuation.
What is oxytocin?
Oxytocin is known as the ‘bonding hormone’.
What is the role of oxytocin in sex?
Oxytocin stimulates lactation.
What is the role of oxytocin in gender?
Oxytocin enhances pair bonding, attachment, and caregiving behaviour, and reduces stress by lowering cortisol.
What is Klinefelter’s Syndrome?
Klinefelter’s Syndrome (XXY) affects 1 in 660 biological males (extra X chromosome).
What are the physical characteristics of Klinefelter’s Syndrome?
Physical characteristics include tall stature, long limbs, reduced facial hair, small testes, and breast development.
What are the psychological characteristics of Klinefelter’s Syndrome?
Psychological characteristics include cognitive difficulties (e.g. dyslexia), passive behaviour, and sometimes emotional outbursts.
What is Turner Syndrome?
Turner Syndrome (XO) affects 1 in 2000 biological females (missing second X chromosome).
What are the physical characteristics of Turner Syndrome?
Physical characteristics include short height, webbed neck, wide chest, and no menstruation (sterile).
What are the psychological characteristics of Turner Syndrome?
Psychological characteristics include high verbal skill but low visual-spatial ability, often leading to social immaturity.
What is a practical application of hormone therapy?
Hormone therapy (e.g. testosterone for KS, oestrogen for TS) improves puberty, mood, learning, and overall wellbeing.
What does the study by Van de Beijsterveldt et al. (2006) suggest?
The study found 70% of variance in gender identity could be explained by genetics, suggesting atypical gender identity is heritable and biological.
What did Theisen et al. (2019) find?
The study found 21 gene variations linked to sexually dimorphic brain regions, suggesting prenatal hormone exposure affects brain development.
