Describe the interactions between genes and the environment in the sex determination of some ...

Maleness and femaleness are determined by complex interactions between genes and the environment. Sex determination in some reptiles illustrates the role of environmental factors in determining sex. The internal temperature of the nest in which the eggs develop determines the sex of the offspring. In some species, higher temperatures produce females and lower temperatures produce males. In other species, the opposite is true. From the study of humans, it is clear that someone having an XX or XY chromosome set does not always mean someone develops as a female or male. The outcome depends on the distribution and expression of genes on the X and Y chromosomes and interactions between genes on these chromosomes with many different environmental factors.