From ArticleWorld

While the term, sex, can refer to the sexual act, this article refers instead to the particular characteristics an individual has that lead to “maleness” or to “femaleness”. The term is related to “gender”, although gender is related more to one’s identity than to biology.

Human Sexes

Unlike plants, which generally carry aspects of both sexes, humans and most animal species are divided into male and female sexes. In humans, the sex is almost always determined by the sex chromosomes. Females carry the XX combination of chromosomes which carry the genetic coding involved in creating female characteristics. In the male, the XY chromosome combination leads to the creation of a male.


Some people are born with a given set of genetic chromosomes but, through errors in development, are born with either ambiguous genitalia or with sexual characteristics that appear to be those of the opposite sex. This is called sexual discordance. This disorder can be a psychologically painful and confusing condition for both the affected child and the family. Decisions must be made as to what gender to assign to the child and what, if any, surgery is necessary to correct anomalies. Other children can be born displaying genital features of both sexes equally.

Sex Characteristics

Sexual characteristics can be either primary (visible at the time of birth) or secondary, occurring as a result of hormonal changes in puberty. Females carry the primary sexual characteristics of a vulva, uterus, fallopian tubes and ovaries. Upon estrogen dominance in puberty, the primary sexual characteristics develop further, menarche occurs and hair develops in the axillae and in the area of the mons pubis.

Male sexual characteristics at birth include the penis, scrotum and the testes. At puberty, testosterone becomes prominent, resulting in the development of facial hair, male body shape and hair growth in the axillae and in the groin. The ability to become sexually aroused, to maintain an erection and to make mature sperm occurs at the time of puberty as well.

Collectively, the presence of the correct sexual anatomy and optimal sexual functioning of both sexes, together with vaginal sexual intercourse, are required for adequate reproduction to occur. The end result, of course, is the perpetuation of the species which, in the case of humans, is that of the Homo sapien.