Developing Teaching Materials using LED for a Phototaxis in Euglena

Abstract

In order to demonstrate the occurrence of the phototaxis to high school students in a clear manner, an experiment using Euglena was improved. In this experiment, a compact apparatus was devised. Several Light-Emitting-Diodes (LEDs) containing white, blue, yellow, and red were used as the light source in the apparatus. The improved experiment using the newly devised apparatus was tested in four 10th grade science classes. The students obtained good results. It was confirmed by students' reports that they could realize the phototactic phenomenon of Euglena. They also considered that there might be some relationships between the action spectrum for phototaxis and the absorption spectra of chlorophyll pigments.