‘Sex' and 'gender' are often used interchangeably, despite having different meanings:
Sex refers to a set of biological attributes in humans and animals. It is primarily associated with physical and physiological features including chromosomes, gene expression, hormone levels and function, and reproductive/sexual anatomy.
Sex is usually categorised as female or male but there is variation in the biological attributes that comprise sex and how those attributes are expressed. For example, someone who is intersex is born with reproductive or sexual anatomy that doesn’t fit the societal assumptions about what constitutes male or female.
Gender refers to the socially constructed roles, behaviours, expressions and identities of girls, women, boys, men, and gender diverse people.
Gender identity is not confined to a binary (girl/woman, boy/man) and refers to a personal perception of gender that can change over time. Someone whose gender identity and/or gender expression differs from the sex they were assigned at birth may identify as Transgender.
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