Video Transcript
If an embryo has a Y chromosome,
what will start to happen around seven weeks into pregnancy? (A) Nervous signals will be
generated to stimulate the development of female secondary sexual
characteristics. (B) The embryo will divide rapidly
into a large mass of cells. (C) The embryo will implant into
the uterus wall. (D) Hormones will be released to
initiate the formation of the male reproductive organs.
This question asks us about the
contribution of the Y chromosome to the development of the embryo during
pregnancy. The Y chromosome is involved in the
development of males who have one copy of the X chromosome and Y chromosome, while
biological females have two copies of the X chromosome.
Both male and female embryos
develop in a similar way during the first six to seven weeks following
fertilization. Then, the Y chromosome in the
embryo will begin to influence further development. The Y chromosome contains the SRY
gene, also referred to as the male-determining gene. This gene will help release certain
hormones that are responsible for the development of male reproductive organs.
Therefore, the correct answer
choice is (D). Hormones will be released to
initiate the formation of the male reproductive organs.