A Maturity-Time Representation for Cell Populations

A maturity-time representation for the study of cell populations is introduced, which differs from the age-time representation suggested by von Foerster. A significant feature of the theory is the concept of maturation velocity. A solution to the fundamental equations of the theory is presented in terms of the individual generations which make up the population at any time. The problem of variability of generation time is considered from the differing viewpoints of the two representations, as well as that of an alternate theory due to Stuart and Merkle. The experimental observations of Prescott concerning the generation time distribution and population growth of Tetrahymena geleii HS cells appear to support best the theoretical formulation of the maturity-time representation. In particular, they suggest that memory of the maturation velocity or generation time of a given cell tends to persist from parent to daughter for several generations at least.