Shape step one.5 . Inside ESD dogs such turtles, gonad differentiation was affected by temperature (A). When you look at the GSD animals, numerous methods for gender commitment had been known. Inside Drosophila, gender is dependent upon new ratio of sex chromosomes to autosomes and you may calculated cell autonomously (B). From inside the mammals, sex is determined mostly from the intercourse chromosome and you can secondarily from the this new hormone influenced by intercourse family genes (C).

Into the GSD animals, the major grounds impacting gender dedication originates inside, particularly, the latest genes harbored for the dimorphic intercourse chromosomes. not, as the intercourse types of is created at the moment of formation of your own zygote, the fresh new sex deciding family genes don’t display instantaneously. Within the pet including Drosophila, intercourse relies on brand new ratio regarding sex chromosomes in order to autosomes and determined structure autonomously ( Fig. step one.5 B). From inside the animals, a man-deciding gene SRY expresses in the event the germ tissues move into intercourse cords, and therefore starts the primary gender dedication of male. Into girls individuals who have simply X chromosomes, new deciding gene DAX1 conveys especially in the brand new gender wires so you can initiate number one sex devotion of the females ( Fig. 1.5 C; Gilbert, 2010 ).

Intricate systems having gender dedication in numerous animals are diversified. Читать далее →