Final answer:
In the absence of the SRY gene, germ line cells will develop into ovaries, as the SRY gene's function is to initiate the formation of testes and suppress female structures. Without SRY expression, the default development pathway is toward female reproductive anatomy.
Step-by-step explanation:
In the absence of the SRY gene, which is located on the Y chromosome, germ line cells will develop into ovaries. This is because the SRY gene is responsible for initiating a cascade of events that lead to the development of testes and suppression of female structures. When the SRY gene is not present, the default development pathway of these bipotential cells leads to the formation of ovaries, which will eventually result in the production of estrogen and the development of the full female reproductive system.
Without SRY expression, an embryo's undifferentiated gonadal tissue does not get the signal to develop into testes. Instead, it follows the female developmental pathway and forms ovaries. This process has far-reaching implications on the entire reproductive system, and, consequently, on the sexual differentiation of the embryo.