BSC 1005 Examination

BSC 1005 What is biology? - Answer- the scientific study of life 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 your 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 three 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 questions. Dull-colored males were used in this experiment to ________. - Answer- serve as a comparison (control) group to the brightly colored males Which of the following is the hypothesis of this case study? - Answer- A function of male coloration is to attract females. "Male collared lizards show considerable color variation." This is a(n) ________. - Answer- observation Which of the following conclusions can be drawn from the data? - Answer- Females do not always choose brightly colored males. Humans are composed of ______ cells. - Answer- eukaryotic Science is ________. - Answer- the inquiry-based effort to describe and explain nature What is the difference between discovery science and hypothesis-driven science? - Answer- Discovery science is mostly about describing nature, whereas hypothesis-driven science tries to explain nature. Which of these would be a valid scientific hypothesis? - Answer- Humans and bacteria share a common genetic code. A hypothesis is a(n) ________. - Answer- tentative answer to a question You try to start your car, but it does not start. Which of these is a hypothesis? - Answer- My car's battery is dead. How do hypotheses differ from theories? - Answer- Theories are more comprehensive than hypotheses. The life-supporting environments of Earth include the __________. - Answer- biosphere Which of these is an ecosystem? - Answer- Lake Erie and everything living in it Most plants are __________. - Answer- producers What is the fundamental unit of life? - Answer- cell Which of these is a prokaryotic cell? - Answer- a bacterial cell Imagine that you are a scientist hard at work in a cancer research lab. You and many of your colleagues are hoping to discover new powerful drugs that could prevent deaths from cancer. Your research team has observed that cancer cells have a lower survival rate when exposed to samples of a certain species of fungus. To study this further, your team isolated several chemicals from the fungus, including one known to affect cell metabolism. You hypothesize that it is that chemical that lowers the survival rate of cancer cells. - Answer- Part A - Interpreting graphs The figure shows percent of cells alive as a function of time. Percentage is measured from 0 to 100 percent on the y-axis, and time is measured from 0 to 10 days on the x-axis. There are 2 curves in the graph. Both of the curves start from 100 percent of cells alive at 0 days. The curve labeled no chemical descends slightly to 85 percent at 10 days. Curve labeled chemical treatment descends rapidly to 9 percent at 10 days. Based on your hypothesis, you predict that the chemical isolated from the fungus will successfully kill cancer cells. To test this prediction, you design the following experiment. You isolate cancerous cells from the colon of a patient from North Carolina and culture (grow) the cells in your lab. You divide the cultured cells into four separate culture dishes. You treat two of the dishes with the fungus chemical and the other two with a control solution that does not contain the chemical. Over the next ten days, you collect data on the percentage of cells that remain alive in each culture dish.