2. Cell culture and cell growth curve Cell culture, particularly, animal cell culture is often used in study on the cell growth and dividing, which might reveal many of the basic properties of cells whose study is more difficult within the organism 1)Density-dependent regulation of cell growth and contact inhibition of growth If the conditions in which cells are cultured are optimal the cells will grow rapidly; mammalian cells typically grow in culture with generation times (lag phase) from 12 to 24 hours. And then cells grow rapidly in an exponential (or log phase, and then gradually slow and finally reaches a point where cell growth and division have virtually stopped, even if sufficient nutrients are still present, being in quiescent or stationary phase2. Cell culture and cell growth curve Cell culture, particularly, animal cell culture is often used in study on the cell growth and dividing, which might reveal many of the basic properties of cells whose study is more difficult within the organism. 1) Density-dependent regulation of cell growth and contact inhibition of growth. If the conditions in which cells are cultured are optimal, the cells will grow rapidly; mammalian cells typically grow in culture with generation times (lag phase) from 12 to 24 hours. And then cells grow rapidly in an exponential (or log ) phase, and then gradually slow and finally reaches a point where cell growth and division have virtually stopped, even if sufficient nutrients are still present, being in quiescent or stationary phase