Sex, Gender, and Sexuality
Biological Sex → physical factors that determine the sex of a person
● Sex chromosomes; Female (XX) and Male (XY)
● Sex glands: hormones that release sex hormones needed for reproduction
( ovaries and estrogen; testes and testosterone)
● Primary sex characteristics: changes during puberty directly related to reproduction
- Mature internal organs (uterus/ovaries and egg cells, testes and sperm cells), menarche:
first menstrual period
● Secondary sex characteristics: changes during puberty indirectly related to reproduction
- Increase in fat, defining of waist, increase in muscle mass, deepened voice, facial hair,
Gender does not equal biological sex
● Biological sex, the physical aspects of being male or female, is different from gender, the
social differences between being male or female.
- Most people feel that their gender matches their biological sex
- 1 to 3% of the population reports being transgender, meaning they feel that their gender
is different from their biological sex.
● In addition, gender can extend beyond the two traditional choices of male and female.
- Some people don’t feel especially male or female
- Other people may feel more male in some situations and more female in others.
● We simply do not know how many people experience gender nonconformity
Is biological sex reflected in our brains?
● There are very small differences between the brains of males and females
● These differences are not necessarily caused by sex difference: the social environment
also shapes how our brain develops, and males and females experience different
environments in our society
● According to the gender similarities hypothesis, males and females are similar in most
Why are males more physically aggressive than females?
● Some research has linked physical aggression with levels of testosterone, and males
typically have more testosterone than females.
● Studies find relationships in levels of testosterone, in addition to increased activity in the
amygdala and prefrontal cortex
● However, research on human subjects does not confirm a clear cause-and-effect
relationship between hormone levels and aggressive behaviors
● The effect of testosterone on aggression appears to be mediated by social and cultural
Is there an in between?
● Intersexuality: when an individual does not clearly fall into the binary of being biologically
male or female
- Caster semenya ● Can be due to abnormalities in:
- Sex chromosomes
(Klinefelter syndrome XXY-merging of sperm and egg cell that create combination of XX and XY
to form new zygote)
● The social, cultural, and biological aspects of masculinity or femininity
Gender schemas & stereotypes
● Organizing information about gender into categories such as gender roles or gender
● Gender stereotypes → most commonly held beliefs about gender