Problem 7 - Biology: The Dynamic Science

Question

In the development of the female sex organs: a. all ducts in the 7 -week embryo become Wolffian ducts. b. the \(S R Y\) gene is activated. c. anti-Mullerian hormone is secreted. d. the Mullerian ducts develop into oviducts. e. the mother secretes oxytocin.

Step-by-Step Solution

Answer

The correct statement is D - the Mullerian ducts develop into oviducts.

Step 1: Evaluation of Statement A

Statement A is false. In the development process of the female sex organs, the Wolffian ducts actually disappear. This is because the Wolffian ducts are male structures – they develop into the male reproductive tract in the presence of testosterone. In the absence of this hormone, which is the case in female embryos, these ducts degenerate.

Step 2: Evaluation of Statement B

Dispelling Statement B, the \(S R Y\) gene is active in male development, not female. This gene initiates male sex determination causing the formation of testes instead of ovaries.

Step 3: Evaluation of Statement C

Statement C is inaccurate either. Anti-Mullerian hormone is secreted by the testes in male embryos to suppress the development of the Mullerian ducts, hence not related to female development.

Step 4: Evaluation of Statement D

Now looking at Statement D. This is indeed correct. The Mullerian ducts are structures present during the initial stage of sex organ development in embryos. In female embryos, these ducts persist and form the oviducts (fallopian tubes), uterus, and upper part of the vagina.

Step 5: Evaluation of Statement E

Lastly Statement E, the mother does secrete oxytocin, but it is not directly involved in sex organ development. Oxytocin is a hormone that has numerous roles, most notably triggering contractions during childbirth and facilitating lactation.