[Campbell Biology P.1079] Based on the "Data from the Experiment" table from Alfred Jost's st... | Practice Question

Based on the "Data from the Experiment" table from Alfred Jost's study, what is the most significant conclusion regarding the role of gonads in mammalian genital development?

  • A: Both male and female genital development require specific hormonal signals from their respective gonads.
  • B: The presence of male gonads (testes) is necessary for male genital development, while female development is the default pathway in their absence.
  • C: The removal of embryonic gonads always leads to female genital development, regardless of chromosomal sex.
  • D: Chromosomal sex alone determines genital development, irrespective of gonadal presence.

Explanation

The table shows that XY male embryos, when their embryonic gonads were removed, developed as female. However, XX female embryos developed as female regardless of whether their gonads were removed or not. This indicates that the male gonads testes are required to direct male development, and in their absence or the absence of their signals , the default pathway is female development.