Discuss the influence of biology on gender
Definitions:
Sex: the biological fact of being male or female, which is determined by chromosomes.
Gender: psychological characteristics of male and female
Genes:
Humans have 23 pairs of chromosomes
Sex of baby is determined at conception
Males have XY chromosomes
Females have XX chromosomes
First 40 days after conception, embryos develop in the same way and have female and male anatomy
If ovum is fertilised by a sperm carrying another X chromosome, the gonads develop into ovaries. The male elements of anatomy disintegrate; the female ones thicken and grow into a womb. The external anatomy develops into female genitalia.
If the ovum is fertilised by a sperm carrying a Y chromosome, the gonads cells convert into testes. The male internal organs develop and the female organs disintegrate. External male genitalia develop.
All human embryos would develop into females unless they are masculinised by the Y chromosome.
Hormones:
After the sex chromosomes, the hormones provide the main biological influences on sexual differentiation.
Males and females produce androgens
The male hormone is testosterone
The female hormones are oestrogen and progesterone
Hormone levels can be taken as a measure of masculinisation and feminisation
Under/over exposure to hormones during the critical period (6 to 8 weeks) can affect later gender related behaviour; boys exposed to too little testosterone may become less masculine and girls exposed to large amounts of testosterone may be more masculine.
Hormones from the gonads influence the development of genitalia, the brain and gender behaviour.
By week 8 of gestation, the gonads are producing hormones.
It is hard to establish hormonal influences on behaviour because there are other influences that affect our behaviour such as the nature, nurture debate
Brain differences:
Clear differences can be found in the brain function of adult men and women, particularly the