Wild-type cells of Paramecium teiraurelia have been studied to determine if easily quantifiable biomarkers could be found to change with age. These same biomarkers were then measured using the ftA 3 mutant, one of a class of early death mutants discovered in P. tetraurelia [48], and in the nd7 mutant, which served as a normal life span control. The adjusted daily mean fission rate, the ratio of cell length to cell width, the percentage of total cell volume occupied by total full food vacuole volume per cell, the number of full food vacuoles per cell and the number of all food vacuoles per cell were all shown to decrease with age in wild-type cells. In general, the nd7 mutant showed similar changes in biomarkers with age, as that shown for wild-type cells. The early death mutant, ftA 3, showed similar changes with age, but proportionally over its shorter clonal life span. Therefore, the ftA 3 mutant appears to be a "rapid senescence" mutant. Studies on the number of macronuclear "aging" fragments for all three cell lineages were also included. Finally, macronuclear misdivision estimates were determined and analyzed for all three cell lineages. The early death mutant shows a high frequency of macronuclear misdivision when compared to wild-type cells and the nd7 mutant.
