Let's get one thing out of the way—what is the difference between sex and gender? Sex refers to biological differences such as chromosomes, hormonal profiles, and internal and external sex organs. Gender, on the other hand, describes the characteristics of what is considered masculine or feminine. So gender is essentially the socially defined differences between men and women. It is a bit like gene and environment interactions (nature vs nurture) and just as hard to separate out. In this article, we will use the term ‘gender differences’ as a blanket term for sex and gender differences.