A Comparison of Synchronized Cell Division in Protozoa*

SYNOPSIS. From an equation derived for measuring synchrony in microbial systems, a synchronization index (SI) may be computed, which depends on 3 parameters: (1) fraction of the population undergoing synchronous division; (2) time during which this synchrony of division occurs, and (3) generation time during normal exponential multiplication. Synchronization indices were computed and tabulated for 14 microbial cultures in which cell division was synchronized by different methods. The SI's range from 0.20 to 0.80. In the ideal situation—instantaneous doubling of the cell number in the mass culture—the SI is 1.00.