Jessica Stermanns Blog November 1/07

Today we wrote our final exam on the reproductive system. I found that ¾ of the exam had to do with the female reproductive structures rather than the male. You really need to know your hormones for this test, as well as their functions and targets. In total there were 31 multiple choice questions and about 5 written response. The written response was very similar to what we can expect on our diplomas. There was lots of reading, so make sure you are doing active reading while taking your test. I used a highlighter to help me point out the important parts of the exam. The written response question was all about estrogen mimicking compounds. I researched the topic and I found an interesting article written by Belinda Martineu called Fathead Minnows.

The article is all about male fathead minnows, what happens to them in the presence of estrogen-mimicking compounds can be likened to a sex change. Scientists are checking whether a gene normally turned "on" only in female fathead minnows has, because of exposure to certain estrogen mimicking compounds is becoming unnaturally activated in male fish. The exposure of a male fathead to an estrogen-mimicking for only 24 hours can activate an egg-yolk gene that under normal conditions would never become activated in the wild. Given enough of an estrogenic, a male fathead can become "feminized," exhibiting the easily distinguishable physical and behavioral characteristics of the female of its species. More than a hundred synthetic chemical compounds such as estrogen are known to be capable of interfering with the normal processes of the endocrine systems in fish, birds, reptiles, and mammals.
This phenomenon caused me to think about how this might affect our own species, and me personally. I found my info at http://www.coastandocean.org/coast_spring2006/articles/fathead_minnows_1.htm