Lesson 4-role of chromosomes and hormones in sex and gender Flashcards
Mainly DNA in humans
What are chromosomes?
-Made of nucleic acids (mainly DNA in humans)and protein and are found in the nucleus of cells.
how many pairs, female and male, fertilisation.
What do chromosomes determine?
XY and XX
-23rd pair determine babies sex with the chromosome pattern for a male being XY and for female it is XX
-All eggs carry an x chromosome and if the egg is fertilised by a Y chromosome carrying sperm, the children will be a male and if the sperm carries an x chromosome, then the baby will be female.
-
male gonads=testicles female gonads=ovaries
What are gonads?
During prenatal devolopment
Reproductive glands
- identical
- have the ability to either turn into either testes or ovaries
- If Y chromosome is present it produces a protein which causes the gonads to become testes
What are hormones?
- chemical messengers that are released into the bloodstream from glands
1.definition
2.statistics female/male
3.characteristics
4.behaviours
What is the role of testerone?
- Androgen (male sex) hormone
- females have about 10 of the amount found in males
- primary characteristics=penis as brain is masculinised essentially increasing the volume of areas linked to spatial awareness, and increased lateralisation
- secondary characterisitics=deep voice, face and pubic hair, growth spurts
- behaviours=agression,competiveness
Weeks of gestation?
primary/secondary
sex
characterisitics
male/female
What do hormones influence?
- Around 8-20 weeks gestation,these sex hormones then influence the development of primary sex characterisitics (born with)
- masculinisation or feminisation of the brain so an individuals sense of gender and gender related behaviours
- Later during puberty, sex hormones influence the devolopment of the secondary sex characteristicis
1.definition 2.characteritics 3.behaviours
What is oestrogen?
- oestrogen is as female sex hormone
- very small amount in males
- primary sex characteristics=vagina;brain is feminised which increases the volume of areas linked to communication and decreased lateralisation
- secondary sex charactersitics=menstrual cycle, pubic hair,hips widen
- behaviours=emotionality, irritability (especially during PMS), multitasking and cooperation.
key words=released, high,low,reduce,stimulate,perinatally
What is oxytocin?
“love hormone”
links to biological approach
- released in both males and females in relatively low levels day to day (although for females it is slightly higher)
- Released in much higher quantities during intimacy
- Also found in large quantities in females perinatally (during and following childbirth)
- Responsible for stimulating lactation and is involved in reducing post natal stress (by reducing cortisol levels ) facilitating the “maternal instinct” and helps bonding between the mother and the child to occur
- explains the more nurturing and empathetic characterisitics in females from biological perspective
transgender
What did Van Goozen et al.1995 find in his research?
- Founded that transgender women (male-female) who were given oestrogen treatment showed decreases in aggression and visuospatial skills
- Transgender men treated with testesterone showed the opposite effects
What was found in Deady et al.2006 research?
- Conducted a correlational study in which they measured 27 young womens testosterone levels, gave them the BEM sex role inventory with extra questions about their mothering intentions and ambition to have children finding high testosterone levels=low desire for children.
Strength of chromosomes and hormones(Bruce/Brendna/David reimer)
PEEL/ talk about the case study boy-girl due to surgical accident
What does this suggest about the influence of chromosomes
P-supports the role of chromosomes in determining our sense of gender
E-changed from healthy boy into girlat 24 months (after a surgical accident which destroyed his external genetalia)Despite therapy and socialisation to turn him into girl , he never identified with the female gender he had been assigned and after disovering the truth, he quickly reverted back to a male
E-Suggests influence of his chromsomes had hard wired his brain to think and feel ‘male’.
L-Gender is biologically determined and is in our nature.
Strength of chromosomes and hormones (Van Goozen 1997)
hormones
testesterone from female to male.What improved and what was reduced?
P-Van Goozen supported the role of hormones in gender
E-he reported findings of a sample of participants who had transitioned from female to male who had never been given testosterone supplements.Founded that their levels of aggression increased and their visuo spatial skills (typically male traits) were improved but they also had a reduction in verbal fluency(typically a female trait)
E-suggests hormones can influence our gender related behaviours
L-gender is biologically determined.
Strength of chromsomes and hormones (van Leengoed 1987)
P-supported claim that hormones can influence nurturing behaviours in females
E-injected rats (just given birth to a latter of rats) with an oxytocin inhibitor (blocker of oxytocin).Female rats showed limited maternal behaviours compared to controls not given the inhibitor
E-Found maternal behaviours wore off when antagonist wore off
L-suggests oxytocin is important in producing maternal behaviours and in developing the bond between a mother and an infant.
injections/something vs something
Limitation of chromosomes and hormones(Tricker 1996)
P-research support by Tricker
E-43 males weekly injections of either a placebo or testosterone for a period of 10 weeks.
E-There was no significant differences in gender related behaviours were reported.
L-This questions the role of hormones and whether they have influence gender related behaviours and that gender is biologically determined.
Limitation of chromosomes and hormones(reductionist)
P-Too reductionist to claim that a specific hormone or gene(SYR gene) are the sole influence on gender related behaviour.
E-Firstly, the chromosomes and hormones are interacting with each other and upon other hormones/and biological mechanisms which make it very complex and complicated process to investigate and understand.
E-Furthermore, means important social/environmental influences are overlooked, which are likely to influence he psycholgical construct of gender.
