Science 30 January 1999 Grade 12 Diploma Examination

Use the following information to answer the next two questions.It has been hypothesized that some frog species in Oregon are in danger ofbecoming extinct because of increased exposure to ultraviolet radiation.29. An increase in exposure has occurred because ofA. the greenhouse effectB. increases in carbon dioxide concentrationC. the thinning of the ozone layer in the atmosphereD. increases in dioxins and furans in the environmentUse the following additional information to answer the next question.It was hypothesized that ultraviolet radiation damages the eggs of sensitivespecies. In an experiment to test this hypothesis, eggs from a sensitive speciesof frog were divided into two groups. One group was shielded fromultraviolet rays with special filtering. The other group was not shielded. Thenumber of eggs that survived in each group was recorded.Parts of the Study1 Uncovered frog eggs2 Percentage of eggs surviving3 Covered frog eggs4 Species of frogNumerical Response07. Match the parts of the study, as numbered above, with the following terms. Use eachnumber only once.Manipulated variable _____ (Record in the first column.)Responding variable _____ (Record in the second column.)Controlled variable _____ (Record in the third column.)Control group _____ (Record in the fourth column.)(Record your answer in the numerical-response section on the answer sheet.)18