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The measurement of an exponential bacterial growth curve in batch culture was traditionally a part of the training of all microbiologists; the basic means requires bacterial enumeration (cell counting) by direct and individual (microscopic, flow cytometry [1]), direct and bulk (biomass), indirect and individual (colony counting), or indirect ...
The theory behind the diauxic growth curve stems from Jacques Monod's Ph.D. research in 1940. A simple example involves the bacterium Escherichia coli (E. coli), the best understood bacterium. The bacterium is grown on a growth media containing two types of sugars, one of which is easier to metabolize than the other (for example glucose and ...
Figure 1: A bi-phasic bacterial growth curve.. A growth curve is an empirical model of the evolution of a quantity over time. Growth curves are widely used in biology for quantities such as population size or biomass (in population ecology and demography, for population growth analysis), individual body height or biomass (in physiology, for growth analysis of individuals).
This open system allows researchers to maintain the exponential growth phase of cells for use in physiological experiments. [ 1 ] A chemostat (from chem ical environment is stat ic) is a bioreactor to which fresh medium is continuously added, while culture liquid containing left over nutrients, metabolic end products and microorganisms is ...
Moreover, the function makes use of initial growth rate, which is commonly seen in populations of bacterial and cancer cells, which undergo the log phase and grow rapidly in numbers. Despite its popularity, the function initial rate of tumor growth is difficult to predetermine given the varying microcosms present with a patient, or varying ...
Incubation follows a growth curve variable for every microorganism. Cultures follow a lag, log, stationary, and finally death phase. [6] The lag phase is not well known in microbiology, but it is speculated that this phase consists of the microorganism adjusting to its environment by synthesizing proteins specific for the surrounding habitat. [6]
The standard logistic function is the logistic function with parameters =, =, =, which yields = + = + = / / + /.In practice, due to the nature of the exponential function, it is often sufficient to compute the standard logistic function for over a small range of real numbers, such as a range contained in [−6, +6], as it quickly converges very close to its saturation values of 0 and 1.
Pathogenic exogenous bacteria can enter a closed biological system and cause disease such as Cholera, which is induced by a waterborne microbe that infects the human intestine. [2] Exogenous bacteria can be introduced into a closed ecosystem as well, and have mutualistic benefits for both the microbe and the host. [1]