Определение и Значение "test tube"

What is a "test tube"?

A test tube is a small, glass or plastic tube used in laboratories to hold, mix, or heat liquids and chemicals during experiments. It is usually cylindrical, with a rounded bottom and an open top. Test tubes are often used to conduct small-scale reactions or to observe changes in substances. They are typically held in a test tube rack to keep them upright and can be easily handled with test tube tongs or clamps when heated. Test tubes are commonly used in science classrooms, research labs, and medical testing.