Question

What is the chance that a human zygote will receive one X and one Y sex chromosome during fertilization?

Answer 1

50 percent or one half

Answer 2

The right answer is 50% (a half).

The sperm that fertilizes the egg (X chromosome carrier) can carry both an X chromosome or a Y chromosome, so the chances are equal, which means that there is as much chance that fertility gives birth to a girl (two X chromosomes) than to give birth to a boy (X and Y chromosome).