Abstract
The contribution describes a design of a laboratory practice in microbiology for secondary schools. Students can test the ubiquity of microbial agents and can test antibacterial disinfectants in this exercise.
It is appropriate to include topics of instruction cells and cellular organisms, which are included in the subject matter of the first year at grammar school. The whole experiment is divided into four labs due to longer incubation of microbial agents.
When performing the experiment, it is necessary to keep the principles of work safety.