MICRB 107 Lecture Notes - Lecture 2: Serial Dilution, Petri Dish, Scattering
Document Summary
Absolute number: the total number of microbes in the entire sample. Concentration number: the number of microbes per unit volume. Using a microscope and specially designed slide to count the number of bacteria. Central regions of slides (kemocyometes or petroff-hauser chambers) are etched with lines with known length and width this region is lower than the surroundings. This is so when a coverslip is placed over the region, the grid that. Number of cells within this area divided by volume of the chamber = number of is seen in the microscope defines a known volumes space cells per ml in the sample. This is not viable count bc we are unable to distinguish between live and dead cells. An instrument that measure the light scattering property of a cell suspension. A concentrated sample of cells with scatter more light than a dilute sample. Spectrophotometer can detect these differences in the turbidity of a cell.
