Sex Determination in Humans

Humans, like Drosophila, have XX-XY sex determination, but in humans the presence of a gene on the Y chromosome determines maleness. The phenotypes that result from abnormal numbers of sex chromosomes, which arise when the sex chromosomes do not segregate properly in meiosis or mitosis, illustrate the importance of the Y chromosome in human sex determination.

Turner syndrome Persons who have Turner syndrome are female; they do not undergo puberty and their female

Table 4.1 Chromosome complements and sexual phenotypes in Drosophila

Sex-Chromosome Complement

0 0

Post a comment