<prompt> Answer this question truthfullyWhat is the central focus of Germinal?  <response>: <reason> The morphology of GCs is very specific and shows properties which are characteristic for different stages of the reaction.In an early state of the reaction a network of FDCs is fully filled with proliferating B cells. Later at day 4 of the reaction GCs show a separation of two zones, the dark and the light zone. The former still contains dominantly proliferating cells while the latter one is the area of B cells selection. These zones dissolve after 10 days of GC development which ends after about 3 weeks. 