Question

Read the assigned article (Pre-natal hormone exposure and sexual variation) and use it to answer the following questions. We are looking for very short but accurate and complete answers, NOT long essays.

1. What factors control the AGDI in rats?

2. IUP has permanent effects on many systems in mice. List four specific effects.

3. An androgen-blocking endocrine disruptor applied during pregnancy will have what effect on male mouse pups?

Answer 1

1. The Anogenital Distance Index (AGDI) is controlled by the distance between the anuss and the genitals in pups, which, in turn, is influenced by the level of testosterone exposed during fetal development. Further, for a female fetus the level of testosterone exposed to her is dependent upon the number of males siblings she is surrounded with.

2. Intrauterine position (IUP) has effects on the followings on female mice:

• Testosterone levels and testosterone sensitivity .
• The age of reaching puberty.
• Behaviors including aggressiveness, attractiveness, mounting behaviour, and mating posture.
• Size of sexually dimorphic portions of the hypothalamus.

3. An androgen blocking endocrine disruptor applied during fetal development will result in reduced play levels, similar to normal females, in juvenile male mice.