Bornstein has a second article that talks about the comparison between sex and gender. Bornstein gives the differences between gender assignment, role, identity, and attribution. Gender assignment is what cultural authorities such as doctors and nurses (but not limited to the general public) say one person's gender is. Gender role is what culture thinks should be done as someone's gender. Identity is a personal feeling by an individual on what their gender is at that time. And finally, gender attribution is the gender we put on people when we first see them. These attributions are based on a variety of cultural indicators such as hair, cloths, biological morphology (breasts, voice), and actions. Different cultures are subject to different gender indicators. She also talks about how the physical act of sex is gendered. She says that the person in whom someone would want to be sexual with depends on gender identity, which links sex to the entire gendering process.
This is a very interesting point! I feel like bathrooms, like locker rooms and other places that are separated by gender, foster a climate of hyper masculinity/femininity within them that can be very exclusive and questioning towards anyone not willing to follow. However, I do think that the separation of bathrooms serves a function in our society. As a compromise, I feel most buildings should have at least one gender neutral bathroom in them. My high school designated one in light of an transgender student's complaints about the conflict he felt in choosing which restroom to pick.