Final answer:
The internal reproductive structures of males and females develop from the Wolffian and Müllerian duct systems respectively. Testosterone and sustentacular cell secretions influence the development of the male system and degeneration of the female system, while their absence allows the female system to develop.
Step-by-step explanation:
Development of Male and Female Reproductive Duct Systems
The internal reproductive structures for males and females develop from two distinct rudimentary duct systems within the embryo. These two systems are known as the Wolffian duct and the Müllerian duct. For males, the Wolffian duct becomes the primary system and develops into structures such as the epididymis, ductus deferens, and seminal vesicles, which are integral to the male reproductive system. This development is stimulated by testosterone and sustentacular cell secretions, which lead to the degeneration of the Müllerian duct.
In females, the absence of testosterone and sustentacular cell secretions allows the Müllerian duct to develop into internal reproductive structures like the uterus, uterine tubes, and part of the vagina. Consequently, the Wolffian duct degrades as it is not needed for female reproductive function. The development or degradation of these duct systems is crucial for proper sexual differentiation and reproductive capability in adulthood.