what does it mean to identify as a gender
Gender identity Gender identity is one's personal experience of one's own gender.[1] Gender identity can correlate with assigned sex at birth, or can differ from it completely.[2] All societies have a set of gender categories that can serve as the basis of the formation of a person's social identity in relation to other members of society.[3] In most societies, there is a basic division between gender attributes assigned to males and females,[4] a gender binary to which most people adhere and which includes expectations of masculinity and femininity in all aspects of sex and gender: biological sex, gender identity, and gender expression.[5] In all societies, some individuals do not identify with some (or all) of the aspects of gender that are assigned to their biological sex;[6] some of those individuals are transgender or genderqueer. Some societies have third gender categories.
XY sex-determination system In humans, half of spermatozoons carry X chromosome and the other half Y chromosome.[3] A single gene (SRY) present on the Y chromosome acts as a signal to set the developmental pathway towards maleness. Presence of this gene starts off the process of virilization. This and other factors result in the sex differences in humans.[4] The cells in females, with two X chromosomes, undergo X-inactivation, in which one of the two X chromosomes is inactivated. The inactivated X chromosome remains within a cell as a Barr body.