Excel Tutorial. Bio 150B Excel Tutorial 1

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1 Bio 15B Excel Tutorial 1 Excel Tutorial As part of your laboratory write-ups and reports during this semester you will be required to collect and present data in an appropriate format. To organize and present this collected data you will need some method to store, manipulate and present this data. Using Microsoft Excel is one convenient method. You may already be familiar with creating spreadsheets in excel, if so you can skip Part I of this tutorial. If not, work through all the parts. I. Creating Spreadsheets Using Excel First, launch a new excel document. In your computers launcher, select the Applications section, and click the Microsoft Excel button. If you have a PC (instead of a Mac) go to the Microsoft Office toolbar (at the top or left of the screen) and click on the green Microsoft Excel icon. This will open a blank spreadsheet with the title Worksheet 1. Each empty box in the spreadsheet is a cell. Cells are identified by column letters and row numbers. Click on A1. This will select that cell and outline it. Let s use the first row to identify our data. In A1, type Time. Click on B1. Type. Click on C1. Type Dissolved Oxygen. If the text typed into a cell overruns the cell border, simply click the cursor on the edge between cells C and D. You will get a double headed arrow. Drag the cursor in the direction you with to expand the cell column. Now we have a simple matrix consisting of three parameters: Time, and Dissolved Oxygen. Click on A2, and type in the initial time. Click on B2 and enter 1. Now click on C2 and enter 345. Complete the data matrix shown below. TIME CELL NUMBER Dissolved Oxygen Now, let s do some simple manipulation of the data. What is the average dissolved oxygen concentration over the 96 hour time period shown? Click on cell C11 and type =Average(C2:C1), then press return. This tells Excel to calculate the average of the numbers entered in cells C2 through C1 and to display that average in C11. Repeat for the cell number data. There are many different functions that Excel can calculate. Click on the f x icon on the Excel toolbar to see a complete listing. II. Creating Diagrams using Excel Once you have entered all your data onto an Excel spreadsheet and done any necessary calculation, you might want to create some diagrams or graphs that illustrate trends among your variable or variables.

2 Bio 15B Excel Tutorial 2 XY Plots If you wish to plot the change in cell numbers in comparison to your time variable in order to see the relationship, use the following method for creating an XY scatterplot. Highlight cells 2 through 1 in columns A and B using your cursor. [Alternatively, if you are having difficulty selecting cells with the drag aspect of the cursor you can highlight the first cell, jold down the shift key and select the last cell in the column and all the cells in between will also be selected and highlighted. This same feature works for rows as well as columns]. From the Excel toolbar click the Chart Wizard icon (the tiny red, blue and yellow bar chart). Select the XY (scatter) option from the menu list on the left. From the Chart Sub-type selections choose the Scatter with data points connected by smooth lines. This will give you a plot of data points against your X and Y axes with a smooth curve joining all the points. Click the preview button to see if it looks correct. Series Now click on Next. This screen shows you the XY plot. At the top it says Data Range indicating that the line with the cursor blinking at its end is the data cells which are being presented on the picture plot. Now click on the Series tab. This moves you to a new screen showing the cells which are being used to create the X and Y axes of your plot. If you wish to plot two lines on the same graph you would click the Add button to create an additional series. We will do this later. Click the next button to continue. This brings you to the Chart Options menu. Here you can add in a Title, labels for your X and Y axes, a legend if you don t have one, or change your gridlines if desired. For now let s just stay with the Title tab. Type in for your chart title. For your Y axis type in. For your X axis type in. Always present units when creating a plot or graph so that others can interpret your data.

3 Bio 15B Excel Tutorial 3 Series Now click next. This brings you to the Chart Location menu. If you want to display the chart or graph next to your raw data click ok. If you would rather display the chart as a separate sheet in your Excel file, choose the As New Sheet option and then click ok. Your graph will open as a full screen sheet. To get back to the raw data spreadsheet, choose the Sheet 1 tab at the bottom of the Excel screen. Plotting an Additional Series In some cases you may want to plot two series of means on the same graph, or you may want to plot a control data point for comparison to your time collected means. Return to your data spreadsheet. In cell A12 type in Stock. In cell B12 type in. In cell C12 type in 345. Now use the bottom tab to return to your Chart. Click on the Chart menu button at the top of the screen and select Source Data. Choose the series tab option. Now click the Add button. In the small box it will show a designation Series 2 which is highlighted. To name this series, type in the appropriate name in the Name box on the right. For this step in our exercise use the designation Stock. Now click on the x-values line and place your flashing cursor in that box. Type ={}. This will put or assign the data the value of on the x-axis so when the point is plotted it will appear on the y axis. Now click on the YValues box. Go to the far right end of the box and click on the small chart with the red arrow. This will condense the Chart Source Data box into a small window open over your graph. If you are not in your data spreadsheet choose the appropriate sheet from the buttons at the bottom. Select cell B12. Click on the red arrow icon to the right end of the Source-Data Values: window. This takes you back to Source Data window. Click OK to view your graph. You graph should appear like the one below.

4 Bio 15B Excel Tutorial 4 Cell Growth Stock Now lets clean up the graph. First click on the dark gray area and use the delete key. This removes the gray background so when you print the graph it is clean and legible. If you wish to change the color or shape of the data point markers double clicking on them will take you to an appropriate menu that allows you to choose different styles and colors. Your graph, like the one above, may have an odd Y-axis scale. To change or adjust the scale of either axis, double click on that axis. Do that for the Y-axis now. Choose the Scale tab at the top. Where it lists Minimum Value change the 5 to. Click on OK to return to the graph itself. Now repeat for the X-axis. In the Maximum box change 12 to 1 and click OK. Use the Dissolved Oxygen data to repeat the tutorial above with a different data set. Try adjusting the axes on your own and manipulating various features of the Chart Wizard function. Create your own data sets and try different graphing styles as well. Bar, column, and line charts might be good ones to also become familiar with for scientific presentation and analysis. Your two graphs based upon the initial data set should look something like the ones below.

5 Bio 15B Excel Tutorial 5 Final Graph; Plot of Cell Growth ( vs. Time): Cell Growth Stock Final Graph; Plot of Oxygen Use (Dissolved Oxygen vs. Time): 4 Culture Media Oxygen Concentration Oxygen Concentration (um) Dissolved O2 Normal Concentration