WHAT IS THE REAL DIFFERENCE BETWEEN MALES AND FEMALES

What determines the sexual differences between male and female mammals ? It is now clear that sexual differentiation is a sequential process. The first step involved the establishment of genetic sex at fertiliza tion. The presence of a particular 'sex determining gene' on the Y chr omosome then controls the development of the testes. In its absence, o varies develop. The final steps involve the testes secreting hormones which control the development of the male reproductive tract. In the a bsence of the testes, the female tract develops. Hormones secreted by the testes or ovaries then control the development of all other other anatomical and phenotypic features characteristic of each sex. This se quential process usually finally produced either males or females with unambiguous sexual characteristics. Occasionally, the normal sequence of events can break down. Depending on where in the sequence the brea kdown occurs, different abnormalities in sexual characteristics are pr oduced.