Yeast cell size is not always constant: under certain conditions, small changes in the average size of cells in a population can occur.
This means that the growth threshold for cell-cycle progression can be reset: larger cells.
For example. The resetting of growth thresholds is best illustrated by the behavior of yeast cells in different nutrient conditions
Cells that grow in a nutrient-rich medium not only grow but are also slightly larger than cells that grow in a nutrient-poor medium.
Yeast maintains a consistent cell size in any given environment by monitoring growth during the cell cycle and restricting proliferation in a size-dependent manner.
However, it is well known that cell size can vary dramatically depending on extracellular conditions.