Which of the following mutations will most likely not result in a change in phenotype of an individual? a. a point mutation which does not change the amino acid b. an inversion mutationc. a nonsense mutation which stops the production of a protein prematurely d. a missense mutation which results in valine being produced instead of glutamic acid ! xoxo

The collared lizard is a species found in the desert southwest. male collared lizards show considerable color variation, ranging from brightly colored to a very dull pattern. your goal is to determine the function, if any, of male color patterns in collared lizards, using the scientific method. your tentative explanation is that male color plays a role in attracting females for mating purposes. you predict that females will preferentially choose brightly colored males over dull-colored ones. to test this prediction, you observed the interactions of female collared lizards with their male counterparts. you selected males that were the same age and size, and that differed only in their coloration pattern. you placed equal numbers of the two types of male lizards, bright and dull, in aquariums, along with one female lizard per aquarium. out of 350 aquariums observed, the female chose to mate with the brightly colored male 277 times, and the dull-colored male 70 times. in 3 instances, the females did not mate with either type. create a bar graph of your data, plotting the type of male (dull or brightly colored) on the x-axis. on the y-axis, plot the frequency with which each type of male was chosen by females. using this graph, answer the following question(s). is it reasonable to conclude (i.e., is it supported by the data) that female collared lizards prefer more brightly colored male lizards over dull-colored males?

Bisphenol a (often called bpa) is a chemical found in products that people use every day, from water bottles to food containers to children's toys. unfortunately, bpa leaches out of its many products and makes its way into our bodies. what are the health effects of bpa exposure? ongoing research is finding that elevated exposure to bpa can affect a wide variety of developmental and physiological processes, but one of the first studies of bpa's health effects came about because of a simple mistake in the lab. at a laboratory at case western reserve university in 1998, geneticist patricia hunt was making a routine check of her female lab mice. as she extracted and examined developing eggs from the ovaries, she began to wonder what had gone wrong. she noticed that many of the eggs showed problems with their chromosomes, and some had irregular amounts of genetic material, which can lead to miscarriages and birth defects in mammals. she learned that a lab assistant had mistakenly washed the plastic mouse cages and water bottles with a harsh soap, releasing bpa from the plastic. knowing that bpa is an endocrine disruptor, a chemical that can enter organisms and mimic hormones, hunt set out to discover whether it had adversely affected her mice.

Which is not a likely outcome after extensive irrigation of dry farmland? useless, unproductive soil salinization of the soil depletion of groundwater nutrient-rich soil