The Graphing Detective: an Exercise in Critical Reading, Experimental Design and Data Analysis

NAME ______DATE ______

The Graphing Detective: An Exercise in Critical Reading, Experimental Design and Data Analysis

ESSENTIAL QUESTION: What can we learn from studying the data from a scientific experiment?

Introduction:

In this exercise you are going to be studying a set of data, in graphical form, which was collected by a scientist, H.W. Harvey, in 1933. His results appeared in the Journal of the Marine Biological Association of the United Kingdom.

The reason for doing this activity is to help you understand that the basis of science is evidence, that is, observations and data collected about the natural world around us. Once the information is gathered scientists then interpret it in order to reach some conclusion or understanding. In this activity you will be interpreting Harvey’s data and trying to identify what the data means and why such data would be collected.

Procedure:

On the attached sheet you will find a graph of Professor Harvey’s data.

STEP 1

Looking only at the axes and data, what do you know about how the study was done?

List your answers in the space below.

(In this step pay no attention to the caption below the graph, nor should you do any analysis of the data.)

Before you move on to Step 2, why is the “oxygen evolved” plotted on the Y-axis rather than the X-axis?

STEP 2

Looking now at the entire graph, including the figure caption, what else do you know about how the study was done?

List your answers below.

STEP 3

What can’t you tell about how this study was done? Or, if you could interview Professor Harvey about his work, what would you ask him?

3a. List your answers or questions below.

3b. Write a paragraph describing, in as much detail as possible, how the study was performed.

3c. Now with two other classmates, compare your paragraphs. Pay particular attention to the accuracy and completeness of the descriptions. What were some of the differences among your three paragraphs?

STEP 4

What specific question is being addressed in the portion of the study represented by this graph?

Remember, the beginning of all science inquiry begins with a question. The question will direct the design of the experiment.

4a. Write what you think Harvey’s question was?

4b. Compare your question to those of your two classmates. Would you make any changes in yours? Why or why not?

STEP 5

Why would anyone want to ask the question referred to in Step 4?

STEP 6

What is the most important result shown by the graph?

6a. Write what you think.

6b. Now, once again, with your two classmates, compare your answers. What are differences in your answers? Is there a correct answer? Why or why not?

STEP 7

Often the results of one experiment, lead to another experiment. This often happens because the results bring up new questions.

What is one new question that the results of this experiment suggest to you?

7a. Write your question.

7b. If you were a scientist, what would be your next step?

This exercise is a slight modification of the one that appeared in “The Graphing Detective: An Exercise in Critical Reading, Experimental Design and Data Analysis,” Pechenik and Tashiro, The American Biology Teacher, Volume 54, No. 7, October 1992