Click on the green flag. A culture of 25 paramecia spawn in the center and move towards the walls of the water container. Click on the orange Push button to create a momentary electric field. The paramecia will be attracted to the push button. See Notes and Credits below.
Galvanotaxis (or electrotaxis) is the movement of an organism in response to an electric field. If platinum electrodes are inserted into a chamber filled with water containing a culture of paramecia, when an electric current is introduced into the chamber, the paramecia move towards the negative electrode. Platinum electrodes are used to eliminate fouling the water and eventually killing the culture. I made a glass chamber with platinum electrodes connected to 1.5 volt AA battery and a push button. It's an amazing sight to see the paramecia interrupt their wandering to turn and head straight for the negative electrode.
