Sexual differentiation in humans Sexual differentiation in humans Sexual differentiation in humans is the process of development of sex differences in humans. It is defined as the development of phenotypic structures consequent to the action of hormones produced following gonadal determination. Sexual differentiation includes development of different genitalia and the internal genital tracts, breasts, body hair, and plays a role in gender identification. The development of sexual differences begins with the XY sex-determination system that is present in humans, and complex mechanisms are responsible for the development of the phenotypic differences between male and female humans from an undifferentiated zygote. Females have two X
Mendelian traits in humans multiple alleles are required from each parent (co-dominant). However the Rhesus factor is truly mendelian because only one allele is inherited from each parent. Rh factor is an antigen on the red blood cell of many people's blood. A positive Rh factor is dominant (presence of antigen) and a negative Rh is recessive (lack of antigen). Blood groups that children may inherit from their parents. Mendelian traits in humans Mendelian traits in humans concerns how, in Mendelian inheritance, a child receiving a dominant allele from either parent will have the dominant form of the phenotypic trait or characteristic. Only those