They write, pick up the telephone, handle money, fix meals, dress wounds. Your hands gather bacteria with each job they do. You can remove many of these bacteria by washing your hands and scrubbing your fingernails. We can't see individual bacteria without using a microscope. But if they are allowed to grow and multiply on agar, we can see them.
Nutrient agar is a special food used to grow bacteria in the laboratory.
It contains everything bacteria need to grow and reproduce. There will be so many that we can see them with the naked eye. These millions of bacteria, side by side, are called a colony. The pictures in this publication show this clearly. We transferred bacteria to agar plates by touching them with our fingers.