67. Brown, Jr. R. M. 1976. Phototaxis der Grünalge Pyrobotrys. Institut für den Wissenschaftlichen film. Wissenschaftlichen Film C 1171/1975 p 3-18. Göttingen.

67. Summary

This film shows a unique phototactic response of the colonial green alga, Pyrobotrys. The most interesting part of the film shows illumination of white light from 180 degrees, causing the alga to swim into a concentrated mass. When the field is viewed with red light (to which the algae do not respond) the algae remain clumped but in relation to the amount of light exposure. This suggests a chemotactic response takes place which is initiated by the phototactic response to light. The proportionality of dose/response is very interesting and seems to indicate that the clumping by intertwining flagellae. The film will soon be in a video format.

For Online Viewing  (1.40 Mb)                

For Printing (7.65 Mb)


Up to the 1976 Publications Page
Up to Malcolm Brown's Lab Page



Last modified 27 October 2005.
This document is maintained by Dr. R. Malcolm Brown, Jr.