What is a petri dish used for?

Petri dishes are shallow, flat, cylindrical or round glass or plastic containers with vertical sides and a flat lid. They are commonly used in laboratories for culturing microorganisms such as bacteria, fungi, and viruses. Petri dishes provide a sterile environment for the growth of microorganisms and allow researchers to observe and study their characteristics.

Petri dishes are typically filled with a nutrient-rich agar gel that provides the necessary nutrients for the growth of microorganisms. The gelatinous substance of the agar allows microorganisms to grow as colonies or "clumps" that can be easily observed and studied under a microscope.

Petri dishes come in various sizes, typically ranging from 50mm to 150mm in diameter. Larger dishes are used for culturing larger colonies of microorganisms, while smaller dishes are used for isolating individual colonies and conducting experiments on a smaller scale.

Petri dishes are essential tools in microbiology laboratories for studying the growth and behavior of microorganisms, testing the effectiveness of antibiotics and disinfectants, and conducting experiments to understand the pathogenicity of various microorganisms.