FIG. 5.

(A) Nomarski photomicrographs of E. huxleyi strain 1516 C cell-to-S cell phase transition over a 48-h period following plating on F/50 media. Magnifications: 0 h, ×564; 12 h, ×677; 24 h, ×752; 48 h, ×677. (B) Rate of decrease in the numbers of C cells present on agar plates during the experiment shown in panel A. The results from four independent experiments were obtained as described in Materials and Methods and showed an average rate of C cell-to-S cell phase transition of 2 to 3% per h on F/50 plates.