The Herbicide Atrazine Is a Known Endocrine Disruptor to the Development

question 27

Multiple Choice

The herbicide atrazine is a known endocrine disruptor to the development stages of several animal species, including fish, reptiles, and amphibians. Scientists interested in studying long-term effects of exposure to atrazine on mating behaviors compared an all-male population of sexually mature African clawed frogs (Xenopus laevis) exposed to atrazine (Atz) to a sexually mature population of African clawed frogs not exposed to atrazine (Con) . Amplexus is defined as the mating position of frogs.

-When considered together, Parts A and C demonstrate

• A) that all frogs in the experiments were male.
• B) a possible explanation for the effect of atrazine.
• C) that testosterone levels are lower in nontreated frogs.
• D) a lack of relationship between successful mating and testosterone levels.