At time = 0,200 ml of broth receives an initial inoculum of bacteria. 0.1 ml of the bacterial culture is taken from the culture at repeated intervals,diluted in liquid agar and spread on a plate containing solid media. After incubation,the plate from time = 420 min yields 62 colonies from the 0.1 ml sample. The total estimated number of cells in the flask at t = 420 min is ________.

Question

At time = 0,200 ml of broth receives an initial inoculum of bacteria.  0.1 ml of the bacterial culture is taken from the culture at repeated intervals,diluted in liquid agar and spread on a plate containing solid media.  After incubation,the plate from time = 420 min yields 62 colonies from the 0.1 ml sample.  The total estimated number of cells in the flask at t = 420 min is ________.

Quizplus · Accepted Answer

The number of colonies on the plate represents the number of bacteria in the 0.1 ml sample. To find the total number of bacteria in the 200 ml flask, multiply the number of colonies (62) by the dilution factor (2000, since 0.1 ml is 1/2000 of 200 ml). Thus, 62 * 2000 = 124,000.

At Time = 0,200 Ml of Broth Receives an Initial Inoculum