The acrosome contains enzymes used to _______________.

A. Penetrate the vagina: The acrosome does not play a role in penetrating the vagina. Its function is specifically related to the sperm's ability to penetrate the ovum, making this option incorrect.

B. Dissolve the stickiness of the semen: While enzymes do play a role in semen liquefaction, this is not the function of the acrosome. The acrosome is primarily involved in the process of fertilization, not semen modification.

C. Dissolve the mucosa of the uterus: The acrosome is not involved in dissolving the mucosa of the uterus. Its function is related to penetrating the barriers surrounding the ovum.

D. Penetrate barriers surrounding the ovum: The acrosome contains enzymes that break down the outer layers of the ovum (such as the zona pellucida), allowing the sperm to penetrate and fertilize the egg. This is the correct answer.

A. Y chromosome: The SRY gene on the Y chromosome codes for the testis-determining factor (TDF), which initiates the development of testes and male characteristics.

B. Gonadal ridges: The gonadal ridges are the precursor structures that develop into gonads but do not contain the gene for TDF.

C. X chromosome: The X chromosome contains genes important for development but does not code for TDF.

D. Fetal testes: The fetal testes produce testosterone but are not the source of the TDF gene.