Name: _______________________________________________________________ Date: ___________ Per: _______
Graphing Lab
Introduction
Graphing is used by scientists to display the data that is collected during a
controlled experiment. A line graph must be constructed to accurately depict the
data collected. An incorrect graph often leads to the acceptance of an incorrect
hypothesis or detract from the acceptance of a correct hypothesis.
The graph should contain 5 major parts: the title, the independent variable, the
dependent variable, the scales for each variable, and a legend.
1.
2.
3.
4.
The title: this shows what the graph is about. Reading the title should give the reader an idea about the graph.
It should be a concise statement placed above the graph.
The Independent Variable: this is the variable (part of the experiment that changes) that can be controlled or
manipulated by the experimenter. This variable should be placed on the horizontal or x-axis. Include units.
The Dependent Variable: this is the variable directly affected by the independent variable. It is the result of
what happens because of the independent variable. This variable is placed on the y or vertical axis. Include
units.
The Scales for each Variable: In constructing a graph, one needs to know where to plot the points representing
the data. In order to do this a scale must be employed that will include all the data points. Maximize your paper
(i.e. make your graph as large as possible). Your scale must be plotted on the amount of graph space available,
and will be dictated by the data points.
The Legend/Key: this is a short descriptive narrative concerning the graph's data. It should be short and to the
point and placed directly under the graph.
Rules



Use a pencil
Use straight lines
Most graphs will have a smooth line although some may have a best fit line.
Part 1
1. The following graph is a fair to good example of a graph. In the t-chart, list what they did well
and what they need to fix?
Good
Bad
2. The graph below is not complete. It is showing the number of bubbles kelp produces at
different depths. What parts is it missing?
3. Add these parts to the
graph.
Graph #1
Use the data below to construct a graph on the next page using the rules above.
Number of French fries eaten
3
8
20
27
40
70
Number of pimples
1
2
8
10
17
28
1. What is the dependant variable? Why did you pick that answer?
2. What is the indepandent variable? Why did you pick that answer?
3. What type of graph would be best for this data?
4. What title would you give this graph?
5. What information would you include in the legend of your graph?
6. What will you label the X-axis with?
7. What will you label the Y-axis with?
Graph #2
Use the following data to create an
appropriate graph and answer the
questions.
Time after eating
(hrs)
0.5
1
1.5
2
2.5
3
4
Glucose in mg/dL
Person A
170
155
140
135
140
135
130
Glucose in mg/dL
Person B
180
195
230
245
235
225
200
Diabetes is a disease affecting insulin producing
glands of the pancreas. If there is not enough
insulin being produced by these cells, the
amount of glucose in the blood will remain high.
A blood glucose level above 140 for an extended
period of time is not normal. This disease, if not brought under control, can lead to severe complications and even death.
1. Which individual would you potentially diagnose as a diabetic?
2. What evidence do you have that supports your answer to #1?