Estrogen and testosterone are key components to understanding the biology behind sexual differences between women and men. Although estrogen and testosterone are present in both sexes, the prevalence of estrogen in women and testosterone in males far outweigh the inverse, resulting in many distinct developments. Here is a brief explanation of how these hormones shape our bodies.

To understand estrogen and testosterone, we first need to understand the role and function of hormones. Estrogen and testosterone are secreted compounds that alter certain receptive organs. Hormones cause other cells, tissues and organs to grow and function differently. When your natural hormones function properly, healthy messages spread throughout your body to create proper development.

Estrogen is a female sex hormone that develops secondary female sex characteristics. Estrogen is produced primarily by the ovaries but also appears from adrenal glands and fat tissues. There are three major types of estrogen in women: estrone, estradiol and estriol. Estrone is the least plentiful of the three major forms of estrogen. Estradiol is more prevalent in women during reproductive ages. During pregnancy, the placenta generates estriol.

Men usually have between 300 and 1,200 nanograms of testosterone per deciliter of blood, whereas women have between 30 and 95 nanograms. Testosterone is the foremost male sex hormone that develops secondary male sex characteristics. It is primarily secreted in the testes and is vital in the development of the prostate. It plays an important role in bone density, fat distribution, red blood cell production, sex drive and sperm production.