This higher expression is likely to cause sex differences in phenotypes. Mysteries of the X chromosome revealed: "silent" X not always mute. By the s, the central idea of 20 th Century sexual differentiation theory was accepted, even though the most definitive experiments were done later, for example by Jost Jost et al.
Understanding the sexome: measuring and reporting sex differences in gene systems. Epigenetic effects of polymorphic Y chromosomes modulate chromatin components, immune response, and sexual conflict. Minireview: Sex differences in adult and developing brains: compensation, compensation, compensation.
There are no examples of temperature-dependent sex determination TSD in birds. Download this article as a PDF. It is unknown how exactly temperature sex determination evolved. Journal of Evolutionary Biology. When one of the X chromosomes of an XX female zygote lags behind in the spindle, one daughter nucleus receives only one X chromosome, while the other receives two X chromosomes resulting in a mosaic body pattern.
In the marine worm Bonellia viridislarvae become males if they make physical contact with a female, and females if they end up on the bare sea floor. The human sex chromosomes: X and Y. Psychological Bulletin, 92 1 Because the animal cannot develop as a hermaphrodite without active tra-1 protein, it develops into a male.
In XO animals the secreted her-1 gene product apparently interacts with the tra-2 gene product, causing it to become inactive.
This inequality leads to male-specific effects of the Y chromosome, including expression of the testis-determining gene Sry that causes differentiation of testes. Introduction: History and Definitions The study of sexual differentiation has undergone dramatic changes in the last half century. The sexual differentiationist studying obesity asks different questions Arnold et al.