سؤال 80

A boy carries one X chromosome and one Y chromosome. Which parent did each of them come from?

The X came from his father and the Y from his mother
Both came from his father, since the mother supplies neither
The X came from his mother and the Y from his fatherپاسخ درست
Either arrangement is possible, since both parents can supply either chromosome

توضیح

His mother has no Y chromosome to give, so the Y he carries can only have arrived from his father, and the remaining chromosome of the pair must then be his mother's contribution. Reversing the two would require a Y chromosome to be present in the mother's cells, which is not part of the female arrangement.

توضیح

ادامهٔ این آزمون