Greeting Scientific Specimens!

It is very exciting that your seedlings are growing and you are collecting your data on your measurements! Great progress!

Nice to see that you’re starting to graph your data. Thank you for posting the graphs! Graphing your data is a part of science that is fun because it allows you to see your results and see if there are obvious differences between your control and experimental groups. When creating graphs, make sure you clearly label with axes, including the units. For example, in your graphs the y-axis is labeled “Angle of curve.” Is that in degrees? If so, it is important to note it like “Angle of curve (degrees)”. Also, your x-axis is labeled “Seed.” What kind of seed? Is this your pea seed or nasturtium seed? This is important because if you are comparing multiple graphs, we want to know you are comparing results from the same type of seed.

You should also begin thinking about what you would like your final graphs to look like for your presentation. Would you like to view all the trials for one sampling date in a single graph? To do this you can add each trial as a separate series (what graphing programs like Excel or Google Spreadsheets call a group of sequential data points). It might take some playing around with formatting your data to do this but you could try something like what I’ve displayed in the spreadsheet titled “All trials, each sampling date” in the Excel workbook called “ScientificSpecimens_sampledatagraphs.xlsx” that I posted in the file section.

You can also graph data from all sampling dates for each trial in a single graph. This way allows you to see the trend in what happened for each seed within each trial. For this setup, you would add each date as a separate series. See the spreadsheet titled “All sampling dates, each trial” in the same Excel workbook to see how you could format your data and what the accompanying graphs would look like. This might be the best way to present your data.

Also, it would be great if you record the angle of the growth that shows which direction it is growing. For example, you can record growing upwards as a positive degrees number and growing downward as a negative degrees number, to show how your experimental seedlings might be zig-zagging in response to your flipping treatment.

Finally, when showing multiple graphs, make sure your axes are the same scale (or range) so you can compare “apples to apples”. For example, if your angle data is between 0 and 60 degrees, then each of your graphs (for each trial) should have a y-axis with a scale (or range) of 0 to 60, even if one trial’s or date’s data is only, say, 10 or 12 degrees. You will see that y-axes in the sample graphs in the document I posted all have the same ranges, from -60 to +60 degrees. Any curves (in degrees) near zero, like the controls, means the seedlings are not responding to gravitropism whereas seedlings with larger curves means the seedlings are responding to gravitropism. This makes sense because the control seedlings are not being moved while the experimental seedlings are growing in different directions based on your flipping treatment. By using negative numbers you can readily see the different directions of growth in the graphs.

You can also use these similar formats to graph other things you are measuring, like seedling length. Just change the axis titles and scales accordingly.

I know this is a whole lot to figure out and understand all at once. Take your time with it and just let me know if you have any questions. Again, you are making terrific progress.

-Allison

Dear Scientific Specimens,

Thank you for posting all the updates. What an exciting development in your experiment to see your seedlings responding to gravitropism! Woohoo!

The files you uploaded with your observations are terrific. You’ve done a great job of describing what you are seeing, and the drawings really help me understand your observations.

Have your nasturtium seeds germinated yet? Nasturtium seeds often need to be soaked for a fair amount of time, like a couple of days, so this might have something to do with why they are not germinating well.

Now that your experimental seedlings have been growing in your flipping treatment for about two days are they responding with your predicted zig zag growth patterns? How are your control plants growing? Are you noticing differences in growth patterns between roots and stems in both your experimental and control plants?

Keep up the great work Scientific Specimens!

-Allison