Transcript Slides as Powerpoint - Department of Biology

Possible Alternatives to Using
an Oscilloscope for Measuring
Action Potential in the
Cockroach Leg Laboratory
Matthew Croft
Somerset High School
Summary
 While the Measuring Action Potential in the
Cockroach Leg Laboratory is interesting and
worthwhile, the equipment is not commonly
found in a typical high school science
department.
 In addition, students may have difficulty
operating oscilloscopes and obtaining data.
 Several alternatives to using oscilloscopes are
discussed.
#1. The Poor Man’s
Oscilloscope
Introduction
 Source: www.ledametrix.com/oscope/
 It may be possible to construct a poor man’s
oscilloscope using a 3.5mm audio cable that has
been separated into three wires and attached to
fine pins:
Measuring Action Potential
 Oscilloscope Software
 Example:
 Audio Editing Software
 Examples:
Measuring Action Potential
 Sample Data from Audacity:
 Speaker (similar to what we did in lab without
the oscilloscope)
Benefits & Drawbacks
Benefits
Drawbacks
Oscilloscope
Software
-Closest to original lab
-Quantitative data with
graph
-Data can be saved
-Purchase of Software
-Possible damage to
computer
-Signal is not amplified
Audio Editing
Software
-Free software is available
-Quantitative data with
graph
-Data can be saved
-Data is not collected in mV
-Possible damage to
computer
-Signal is not amplified
Speakers
-Audio response can be
rewarding to students
-Data is not quantitative
-Probably not feasible
without amplifier
#2. Multimeter
Introduction
 It may be possible to measure action potential
on a multimeter set on mV.
Benefits & Drawbacks
Multimeter
Benefits
Drawbacks
-Readily available
-Easy to use
-May not be sensitive
enough
-Data is not displayed in
graphical format
-Signal is not amplified
#3. Vernier Sensors
Introduction
 Vernier LabPro and LabQuest allow you to use a
wide variety of sensors to collect information.
Data can be analyzed in LoggerPro.
Possible Sensors
 Voltage Probe
Possible Sensors
 EKG Sensor
Benefits & Drawbacks
Benefits
Voltage Probe
EKG Sensor
-Comes standard with LabPro
-Quantitative data with graph
-Will not damage computer
-Data can be saved and
LoggerPro allows for
advanced data analysis
-Quantitative data with graph
-Will not damage computer
Ulf
thinks
-Three
leads it
-Measurements
are in mV
will work!
-Data can be saved and
LoggerPro allows for
advanced data analysis
Drawbacks
-Purchase of Hardware &
Software
-Probe may not be sensitive
enough
-No ground wire
-Measurements are in V
-Purchase of Hardware &
Software
-Probe may not be sensitive
enough