How to Define Sex

Sex is a biological trait which determines the reproductive role of an organism, male or female, both in plants and animals that reproduce through sexual reproduction. The classification of an organism into male or female determines its sex. Sexual organs differ in the sexes. In humans, the testicles and scrotum are the places where the sperm and ovum are stored during reproduction.


Humans have many concepts of gender and sexual behavior. These concepts are socially constructed and therefore subject to change with time. Some of these changes have occurred without the awareness of humankind.

In the animal kingdom, all the species known to have a Y chromosome, the male specie having only one Y chromosome whereas all the species of the female kind have X chromosomes, the female specie having two X chromosomes. The X chromosomes only produce female characteristics. There are no X chromosomes in the male specie, whereas X stands for “sex” since it is responsible for conception. The chromosomes may be X or Y but they are still segregated by gender.

The assignment of sex is also determined according to the Y chromosome being dominant over the others. If the Y chromosome is more dominant, then the specie is classified as male. If the Y chromosome is less dominant, then it will be classified as female. For example, if the X chromosomes dominate, then humans will be categorized as female, while if the X chromosomes are more dominant than the others, humans will be classified as male.

Furthermore, human beings are further divided into two categories according to the relationship between the X-chromosome and the Y-chromosome, or the male and female sex respectively. There is no true inter-sex difference in humans, as the term “inter-gendered” is not used in the scientific community. In terms of biology, it is still possible for inter-sex couples to have children of both genders, as both chromosomes can be passed on to future generations.

Because sex is often thought of as a binary concept, it is very easy to find terms used interchangeably that reflect this division of gender in relation to biological sex. Intersex adults may struggle with understanding their sexual identity. However, the fact that sex is merely a biological distinction does not erase the possibility of people having both female and male characteristics simultaneously. Understanding these definitions can help intersex individuals accept their bodies, and gain a sense of wholeness.