Which of the following biological factors determines the genetic sex of a fetus?
A. The gonads of the fetus B. A single gene on the X chromosome C. The hormones produced by the pituitary during fetal development D. The father s sperm E. The phase of the menstrual cycle during which fertilization occurs
The genetic sex of the fetus is determined by the father’s sperms. This determination is based on the X and Y chromosomes that the men’s sperms carry. For instance, an X chromosome from the man’s sperms combines with the X chromosome from the mother to produce a baby girl having XX chromosomes.
Similarly, a Y chromosome from the man will combine with the X chromosome from the mother to produce a baby boy with XY chromosomes. In many other species, the determination of the genetic sex is far more complex as there are different alleles that result in the difference in chromosomes.