the role of chromosomes and hormones

• when a person is born their sex is characterised by whether they are genetically male or genetically female.
• sex is determined by the XX pair of chromosomes for females, and the XY pair of chromosomes for males
• After conception, the external genitalia of male and female embryos look the same
• as the foetus develops, the internal genitalia of a female produces oestrogen- the primary female hormone that plays a role in the menstrual cycle and reproductive system.
• levels of oestrogen influence the development of gender, higher levels of oestrogen cause behaviours such as emotionality
• oxytocin is another hormone that influences gender development- women produce this hormone in larger quantities than males
• oxytocin is connected to nurturing and maternal behaviours that are stereotypically associated with a female identity
• as the foetus develops, the internal genitalia of a male will produce testosterone
• Turner's syndrome in girls- psych symptoms- low visuo-spatial skills, poor mathematical ability, social immaturity, good verbal skills and reading ability,
• Klinefelter's syndrome- when a boy is born with an extra X chromosome (XXY), physical features- taller than average/long legs, development of breasts, reduced hair growth, underdeveloped testes, low testosterone production
• Klinefelter's in boys- psychological features- good maths skills, poor reading and verbal skills (dyslexia), behavioural passivity and is easily upset, difficulty in problem solving,
• Females have two pairs of X chromosomes, whereas males have one X chromosome and one Y chromosome. It is genes in the Y chromosome that are responsible for male development, such as the formation of testes and higher levels of the hormone testosterone.
• klinefelters in boys- born with xxy rather than xy sex chromosomes, affects roughly one in 750 males
• testosterone- he primary sex hormone in males. On average, men have around 10 times as much testosterone as women. These higher testosterone levels have psychological effects that contribute to gender differences.
• oestrogen- . Estrogens are associated with female development, with women typically having 10 times as much estradiol as men. These higher estrogen levels contribute to gender differences.
• Estrogen is associated with stereotypical female behaviours, such as compassion and sensitivity. After puberty, estrogen also regulates the menstrual cycle in women
• Oxytocin is sometimes called the ‘love hormone’ because it is associated with bonding, nurturing, trust, and sociability. Oxytocin levels are typically higher in women than men and the effects of oxytocin are amplified by estrogen, so oxytocin contributes to gender differences.
• Oxytocin plays an important role in childbirth by causing contractions. After the baby is born, oxytocin stimulates lactation to enable breastfeeding. Oxytocin also helps form an emotional bond between mother and baby.
• Wagner (1980) castrated male mice which reduced aggression in behaviour, when injected with testosterone aggression returned, these animal studies are often used due to experimental control and avoiding ethical issues
• chromosomes hold your genotypes, genetic information
• genotypes- code for physical and behavioural characteristics,
• female - xx, male- xy
• Hormones- biochemical messengers that are released from glands into the bloodstream, when in the bloodstream they can influence the functioning of other bodily organs and systems
• testosterone- an androgen- meaning a male sex hormone, 10x more in males than females, responsible for the development of a male foetus, linked to higher levels of aggression
• oestrogen- female sex hormone, higher concentrations found in females, help regulate the menstrual cycle and development of secondary sexual characteristics
• oesgtrogen role in gender- high levels after giving birth linked to maternal caregiving behaviour and reduction in oestrogen levels implicated in feelings of irritability
• oxytocin- stimulates lactation in females- sex role. role in gender- caring/attachment behaviour in females
• XXY- klinefelter's syndrome (males), x0- turner's syndrome (females),