Chromosomes and hormones Flashcards
(23 cards)
What are chromosomes made from?
DNA
What are genes?
Short sections of DNA that determine characteristics of a living thing
How many chromosomes are there in the human body and how are they arranged?
46
23 pairs
What does the 23rd pair of chromosomes determine?
Biological sex
What determines the babys sex?
The sperm that fertilises the egg
Egg always contains X chromosome
If sperm carries X - female
If sperm carries Y - male
What gene do the Y chromosomes carry and what does it do?
Sex determining region Y (SRY)
Causes testes to develop in an XY embryo
What are androgens?
Male sex hormones
What do hormones do prenatally in the womb?
Act upon brain development
Cause development of the reproductive organs
What happens at puberty?
A burst of hormonal activity triggers the development of secondary sexual characteristics like pubic hair
What does testosterone control?
The development of male sex organs
What happens if a genetic male produces no testosterone during foetal development?
No male sex organs appear
What happens if a genetic female produces high levels of testosterone during foetal development?
Male sex organs may appear
What are high levels of aggression associated with according to the evolutionary explanation?
Aggression because it is adaptive
Allows males to compete for the opportunity to mate with a fertile female
Men more likely to take on hunter role
What does oestrogen determine?
Female sexual characteristics and menstruation
What is premenstrual tension/ syndrome?
When effects like heightened emotionally and irritability become a diagnosable disorder
What does oxytocin stimulate?
Lactation
Reduces stress hormone cortisol
Facilitates bonding
When is oxytocin produced?
Massive quantities during labour and after childbirth
What did men producing less oxytocin fuel?
Stereotypes that men are less interested in intimacy and closeness within a relationship
What does newer evidence show about oxytocin?
Both sexes produce equal amounts during amorous activities such as kissing and sexual intercourse
What is a strength of the roles of sex hormones in gender development?
Evidence for testosterone
Wang et al
Male hypogonadism - mans tetstes fail to produce normal levels of testosterone
227 hypogonadal men testosterone therapy for 180 days
Changes in body shape, muscle strength, sexual function etc all monitors across period
Improved sexual function, libido and bood, increase in muscle strength observed
Shows testosterone exerts powerful and direct influence on male sexual arousal and physical development in adulthood
What is a negative of the roles of sex hormones in gender development?
Oconnor et al
Double blind
Placebo
Increased testosterone levels in healthy young men
No significant increases in interactional or non interactional components of sexual behaviour in participants
Men experiences no change in aggression or anger levels
Additional testosterone may have no effect on sexual or aggressive behaviour
Doesn’t challenge role of testosterone in early development
What is a weakness of the roles of sex hormones in gender development?
Ignores role of social factors
Hoftede et al
Gender roles around world are much more consequence of social norms than biology
Individualistic vs collectivist
Individualist - masculine outlook
Challenging biological explanation of gender behaviour
Social factors more important in shaping gender behaviour and attitudes
What is a weakness of the roles of sex hormones in gender development?
Reductionist
Reduce to chromosomes and hormones
Cognitive approach - influence of the thought process like schema
Psychodynamic approach - maturation as a factor but more importance of childhood experiences
Suggesting that gender is more complex than biological influences alone
