GENETICALLY MODIFIED SOYBEANS VERSUS TRADITIONAL SOYBEANS HOW DO THEY COMPARE? Do genetically modified soybeans look different form traditional ones? Can we detect a difference in how they grow and respond to environmental stimuli? Equipment and Supplies Needed* Traditional Soybeans and Roundup Ready Soybeans purchased at your local seed store. 40 plastic circular planters filled with soil Herbicide Roundup Weed Seeds (mustard seeds) *Note: A kit with all necessary materials is available from Carolina Biological: 1-800-334-5551. PROCEDURE Day 0 Plant 1 GM soybean in each of 20 planters and mark those planters GM to indicate that they contain genetically modified seeds. Place 1 traditional soybean in each of 20 different planters and mark the planters T to indicate that they contain traditional seeds. Continuously provide plenty of light and water. On even numbered days, count the number of seeds that have germinated and record the color of the plants. In addition, measure the heights of the plants that have germinated, and calculate the average height. Record all measurements and observations in the table below. Day 5 Add the same amount of weed seeds to each planter. Continue to observe and water the seedlings. Day 15 Apply the Roundup herbicide to soybeans in each pot. Day 22 Final day to take measurements and record observations. DATA ANALYSIS Use Microsoft Excel or graph paper to graph the mean height of plants over time for both the genetically modified and traditional soybeans. A single line graph will probably be most effective for this activity. Instructions for how to make a line graph in Excel are below. Have students prepare a lab report outlining the procedures used, the results, and the significance of their findings. Students can use the graph that they prepared in the results section of the lab report. 84 DESTINY - UNC-CHAPEL HILL - CB# 3280, Coker Hall - Chapel Hill, NC 27599-3280 - (919) 843-9036 - www.destiny.unc.edu
TABLE 1 Record the mean height, color, the number of seeds germinated, and any observations on even numbered days from day 2 through day 22. On day 5, plant weeds, on day 15, plant weeds and record any observations. Day Genetically Modifi ed Soybeans Traditional Soybeans Mean Height Color # seeds germinated Observations Mean Height Color # seeds germinated Observations 0 Seeds Are Planted Seeds Are Planted 2 4 5 Plant Weeds Plant Weeds 6 8 10 12 14 15 Apply Herbicide Apply Herbicide 16 18 20 22 DESTINY - UNC-CHAPEL HILL - CB# 3280, Coker Hall - Chapel Hill, NC 27599-3280 - (919) 843-9036 - www.destiny.unc.edu 85
Graph paper 86 DESTINY - UNC-CHAPEL HILL - CB# 3280, Coker Hall - Chapel Hill, NC 27599-3280 - (919) 843-9036 - www.destiny.unc.edu
INSTRUCTIONS FOR USING EXCEL TO GRAPH YOUR DATA 1. Go to the Programs Menu and open Microsoft Excel. a. A spreadsheet will appear on the screen. 2. In cells A1, B1 and C1; type in your labels (Day, GM soybeans, and Traditional soybeans) a. In cells A2- A12, type in day numbers. b. In cells B2-B12, type in the mean height of the GM soybeans for the corresponding day. c. In cells C2- C12, type in the mean height of the Traditional soybeans for the corresponding day. 3. Highlight columns B and C including the labels in cells B1 and C1. a. Click the Chart Wizard tool button on the right side of the Formatting Toolbar, or choose Chart under the Insert menu option. DESTINY - UNC-CHAPEL HILL - CB# 3280, Coker Hall - Chapel Hill, NC 27599-3280 - (919) 843-9036 - www.destiny.unc.edu 87
4. In Step 1 of 4: Select chart type (Line). Select the sub type you would like, and then click the Next button 5. In step 2 of 4: Select column in the series in choice. Then choose the series tab. Mouse click one time in the Category (X) axis label blank, and when the cursor is in the blank, highlight the day numbers (cells A2 through A12). Click next button. 88 DESTINY - UNC-CHAPEL HILL - CB# 3280, Coker Hall - Chapel Hill, NC 27599-3280 - (919) 843-9036 - www.destiny.unc.edu
6) In step 3 of 4, fill in the chart title, as well as labels for X and Y axes. Click Next. 7) Choose the As new sheet: option and give the chart a title. Click Finish. DESTINY - UNC-CHAPEL HILL - CB# 3280, Coker Hall - Chapel Hill, NC 27599-3280 - (919) 843-9036 - www.destiny.unc.edu 89