7. Do bacteria age?

Yes. Bacteria can age at the level of lineages and cell poles, even when cell division appears symmetric. Old-pole cells and cells that inherit aggregated or damaged components often show slower growth, reduced offspring output, and higher death risk, while their siblings that inherit less damage are relatively rejuvenated. This makes bacterial populations a clear case where “immortality” arises from continuous rejuvenation of progeny, not from absence of age-related burden.