ex vivo microbiological method plate count 2015-05-01T11:55:30Z JSmith MMO:0000563 The enumeration of individual colonies in a microbial/bacterial culture by distributing a solution containing the microorganisms, either straight or (more commonly) as a set of serial dilutions, onto a dish containing a base layer of growth medium plus a gelling agent such as agar. At an appropriate dilution, each viable microorganism will divide to form an individual, clonal colony. The number of colonies on each plate is counted and, using the volume and dilution of the plated sample, the absolute number or the concentration of microbes in the original sample is calculated. colony count colony counting method measurement_method_ontology plate counting method