Squid Axon

an interactive computer simulation of the isolated giant axon of the squid for teaching undergraduate students

David Dewhurst, Euan Brown & Alan Williams


This program simulates a number of experiments, which may be performed on this preparation to investigate the biophysical properties of nerve.

1. The METHODS section uses a combination of text and high-resolution colour graphics to describe the preparation, the apparatus used to record the resting potential of the axon and the techniques of current and voltage clamping.

2. The EXPERIMENTS section is highly interactive and may be used to investigate:

The Resting Potential: the student may select, from a menu, to vary the concentrations of Na+ (5-500 mM), K+ (5-500 mM) and Cl - (5-600 mM) in the extracellular fluid and axoplasm, and record changes in the resting membrane potential.

The Action Potential: students may design experimental protocols, which allow them to perform:

Current Clamp experiments where the ECF concentrations of Na+ (5-500 mM); K+ (5-500 mM) and Cl- (5-600 mM) may be varied individually and single or paired stimuli applied. Records of voltage or conductance changes are then displayed.

Voltage Clamp experiments where the student may set a membrane holding potential and up to 3 command potentials to voltage clamp the axon and record membrane current or conductance changes. The ICF and ECF concentrations of Na+ (5-500 mM) and ICF K+ (100-500 mM) may be changed.

Hardware requirements: IBM PC & PS2 compatibles with Hercules, EGA or VGA graphics
Target audience: Undergraduate bio-medical science students
Price: £120 (multiuser/departmental licence)

N.B. This particular title is currently unavailable, but please send an e-mail and we may be able to offer this program by special arrangement.

ISBN 1-874758-20-4
©1989 Sheffield Bioscience Programs

Click on one of the above screen grabs to see full size image.