Metabolic pathways further increase the complexity of cell size control in budding yeast

How organisms regulate their size is a major question in biology. With a few notable exceptions (such as cell divisions in the early embryo), most cells need to reach a critical size in order to initiate a new cell cycle. How cells set a critical cell size, and how they know it has been reached, is not well understood. Using various types of experimental systems, decades ago two main models were proposed for cell size homeostasis: the deterministic model and the probabilistic model.