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
What Kind of an American are You? What Kind of an American are You? What Kind of an American are you?, also known as What Kind of American are you?, is a World War I era song released in 1917. Albert Von Tilzer composed the music. Lew Brown and Charles R. McCarron wrote the lyrics. The song was published by Broadway Music Co. of New York, New York. On the cover is a gray drawing of Uncle Sam pointing. A map of the United States is featured on the lower half of the cover. The song was written for voice and piano. The sheet music can be