What is the primary purpose of a petri dish?

The primary purpose of a petri dish is to culture microorganisms. Petri dishes are shallow, flat, cylindrical containers that often contain a nutrient medium, like agar, which provides the necessary environment for bacteria, fungi, and other microorganisms to grow and multiply. This makes them essential tools in microbiology for conducting experiments and studying various biological processes. The design of petri dishes, typically made of glass or clear plastic, ensures that researchers can easily observe microbial colonies as they develop, which is critical for both educational and research purposes.

While other options mention storing chemicals, measuring volumes, or holding samples, they do not accurately reflect the specialized use of petri dishes in biological laboratories. The ability to create controlled environments for microbial growth is what sets petri dishes apart as vital instruments in scientific inquiry.