“Wormbeat”: A Lab to Introduce the Scientific Method
BACKGROUND FACTS (write in complete sentences; facts describe what you MUST know in order to conduct the lab & understand the data):
1)
2)
3)
INTRODUCTION
QUESTION (reread your Pre-Lab information):
HYPOTHESIS: If the heart rate of earthworms is affected by temperature, then ______.
IDV:
DV:
CONTROLLED VARIABLES:
Control (in a list format) / How the variable was controlled1.
2.
3.
RESULTS (use a ruler!!)
DATA TABLE ____: ______
(#)(include DV and IDV to write a descriptive title)
DATA TABLE ____: ______
GRAPH #1: ______
(include DV and IDV to write a descriptive title)
CONCLUSION
1) What is the correlation between temperature & an earthworm’s pulse rate?
2) State the class averages (final processed data) for both temperatures. Be sure to include units!
3a) Why do these results make sense in light of the fact that earthworms are ectothermic?
3b) Would these results hold true for humans? Explain.
ERRORS & MODIFICATIONS
When determining experimental errors, there is a difference between human errors & procedural errors. Human errors are mistakes made by the experimenter while trying to follow the written procedure. Procedural errors occur because the steps of the experiment are not detailed enough which results in the experiment not being completely controlled (refer to notes for clarification on “controlled variables”). In order to determine procedural errors, re-read the procedure and think about each step. Was the step hard to do (why?) or what information was missing in this step?
In the table below, you’re going to identify examples of these two types of errors. After you identify the procedural errors, modify that step of the procedure. An example of each has been given to get you started.
HUMAN ERRORS / PROCEDURAL ERRORS / MODIFICATION TO PROCEDURECouldn’t count the pulse / Difficult to count because the worm moves too much / video the experiment so the image can be enlarged & replayed in order to count pulse rate
1. / 1. / 1.
2. / 2. / 2.
3. / N/A / N/A