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Bacterial Growth Curve Virtual Lab

Phases of bacterial growth with scientist Cindy. How do we analyze bacterial growth? It is convenient to create a graph of the number of bacterial cells in our cell culture versus time. This type of graph is called a growth curve. Here is just an example of one possible growth curve. keep in mind that the time in which all of these phases will be experienced will vary depending on the amount of available space and available nutrition and the species of bacteria we are using. all bacterial growth curves grown in cell culture in laboratory exhibit the same 4 following phases” the lag phase the log phase or exponential phase the stationary phase and the death phase the lag phase of the growth curve occurs when we have no active growth. so the population of cells remains the same or constant during the lag phase. this is because the bacteria are adjusting to the new environment the thus, will not undergo binary fission until they have adapted to their new habitat. once they have adapted, we will experience the exponential phase or log phase of our growth curve. This growth is seen because there are plenty of nutrients and plenty of space for growth to occur. This exponential growth or logarithmic growth will eventually level off this leveling off is due to the population of bacteria beginning to run out of available space and available nutrients. also the cells will experience of continued build-up of toxins. due to these factors the log or exponential phase will give way to the stationary phase. In the stationary phase we see that there is no real change in the number of bacteria in the cell culture. This is because, in the stationary phase the number of bacterial cells in our cell culture remain fairly constant due to the fact that the number of cells being created will roughly be equal to the number of cells dying in our cell culture after some time, the depletion of nutrition and space along with the build-up of toxins in our cell culture will cause more cells to be dying themselves that are being produced this gives us our death face of the bacterial growth curve after some time in these conditions you will eventually see that all of our cells in the cell culture will die