What is an example of a physical method of controlling microorganisms?

Autoclaving is a prime example of a physical method used to control microorganisms. This process involves subjecting materials to high-pressure steam at temperatures usually around 121°C (250°F) for a specific duration. The combination of heat and pressure effectively sterilizes the contents, eliminating bacteria, viruses, spores, and fungi. This method is widely used in laboratories and medical fields for sterilizing surgical instruments, culture media, and other materials that must be free from any microbial life.

In the context of microbial control, autoclaving stands out because it employs physical principles—specifically pressure and heat—rather than relying on chemicals to achieve sterilization. This distinguishes it from methods such as chlorination, which uses chemicals to disinfect water, and disinfection with alcohol, which, while effective in reducing microbial load, does not provide the same level of sterilization as autoclaving. Similarly, the application of antibiotics targets specific microorganisms through biochemical pathways rather than physically eliminating them, making autoclaving a clearer representation of a physical method for controlling microbial growth.