culture procedure, (in bacteriology) any of several techniques for growing colonies of microorganisms to identify a pathogen and to determine its sensitivity to various antibiotics. Usually a specimen is secured by using sterile technique and a small amount is placed into or on one or more culture media, because different organisms are nourished by different nutrients and grow best at different specific pH levels. The environment in which the media are held during observation is maintained at body temperature, and the ambient oxygen level is adjusted to achieve an aerobic or anaerobic state. All procedures are aseptic, and all equipment is sterile to prevent accidental contamination of the media. As colonies appear in or on the media, small amounts of each (there are often several) are spread onto other media to allow examination of a pure specimen of the microorganisms.