Answer:
Aseptic technique
Explanation:
Aseptic technique is employed to avoid environmental bacteria (e.g., of bacteria source can be from the air) from infecting cultures. This explains why flaming (fixing the Bunsen burner in such a way that its flame gives an inner and outer cone) of the mouths of the culture tubes is necessarily carried out before and after transferring bacteria. It involves transfer of microbes from pure culture to sterile culture without contamination of oneself, fellow workers, the environment, the source culture, or the medium being inoculated.
