2020 AP Biology Practice Exam and Notes #1 for the Spring ...



Scientists studied soybean plants grown in sunlit, controlled-environment chambers with a carbon dioxide (CO2) concentration of 700 μmol CO2 / mol of air. The CO2 concentration in the chambers was approximately double that of normal concentrations of environmental CO2.Photosynthetic rate is measured by the amount of CO2 exchanged in an area of leaf surface over time. The rate is directly influenced by the activity of the plant enzyme rubisco. During photosynthesis, rubisco fixes atmospheric carbon into an organic molecule as one of the first steps in the Calvin cycle.Scientists measured the amount of carbon fixation that occurred in the leaves of soybean plants grown at each temperature shown in Table 1.Table 1. Carbon Fixation by Rubisco Under Different TemperaturesTemperature (?C)Carbon Fixation?2SE x (μmol / m2/s)2591 ??93096 ??53593 ??840104 ??74571 ??75059 ??4Describe the effect on an enzyme of an increase in environmental temperature above the optimum temperature range of the enzyme.Using the template in the space provided for your response, construct an appropriately labeled graph to represent the data in Table 1. Determine whether there is a statistical difference in the amount of CO2 fixed by rubisco at 30?C and 40?C.Based on the data, identify the temperature range at which the soybean leaves are producing the lowest amount of carbohydrate.Increased amounts of carbon dioxide in the atmosphere are correlated with increased global surface temperatures. Based on the data, predict how a surface temperature that continues to rise above 40?C mostlikely affects the amount of energy available to primary consumers in an ecosystem. Provide reasoning to justify your prediction. One model predicts that an increase in greenhouse gases will lead to a 2?C increase in average surface temperature on Earth. Based on the data from the experiment and the prediction of an increase in average surface temperature by the model, predict how the locations of plant species are expected to change over time. ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download