Practice question

After phototactic migration, slug selects drier spot where ammonia dissipates, enabling culmination phase where anterior prestalk cells undergo programmed vacuolization, synthesize cellulose walls, and crawl down through prespore mass in reverse fountain movement forming stalk tube. Prespore cells ascend and encapsulate into spores atop stalk. This dramatic morphogenetic transition occurs without cell division, relying solely on sorting and terminal differentiation. Vegetative growth precedes aggregation, aggregation precedes migration; spore dispersal occurs only after culmination completes. Culmination therefore represents final architectural construction stage converting migratory slug into stationary fruiting body optimized for propagation.