High‐speed cinematographic analysis of the movement of Chlamydomonas

Using high‐speed microcinematography (100–500 f/s) the movement of Chlamydomonas reinhardtii mutant 622 E has been studied with frame‐by‐frame analysis. The stigma lies in the cell equator, displaced out of the flagellar plane anticlockwise by an angle of about 45°. During forward movement the cells rotate anticlockwise about their long axis with a frequency of 1.4–2 Hz (maximum 2.5 Hz). The rotation is caused by a lateral component of 3‐dimensional beating of the flagella during the effective strokes. The helical swimming path is a result of an unequal flagellar beating. This is normally synchronous, but synchrony is interrupted from time to time by an additional beat of the outward directed flagellum, in our study one after about every twenty beats on average. These results are discussed and compared with the results published by other groups.