"Test tubes" are cylindrical, transparent containers commonly used in laboratories for holding and mixing chemical substances or conducting various scientific experiments. They are typically made of glass or plastic and come in different sizes to accommodate different volumes of liquids or samples.

 

Test tubes have a wide range of applications in various scientific fields, including chemistry, biology, biochemistry, and medical research. They are used for tasks such as sample storage, chemical reactions, heating, centrifugation, and observation.

 

The design of test tubes allows for easy handling and manipulation. They typically have a rounded bottom and open top, allowing for the addition and removal of substances with pipettes or other laboratory tools. Some test tubes may have graduations or markings to measure the volume of liquid contained inside.

 

Test tubes can be used individually or in combination with other laboratory equipment such as racks, holders, or tube stands. They can also be fitted with caps or stoppers to secure the contents and prevent spillage or contamination.

 

In addition to traditional glass test tubes, plastic test tubes have become popular due to their durability, disposable nature, and resistance to breakage. Plastic test tubes are often used when working with hazardous or corrosive substances or when disposable applications are required.

 

Overall, test tubes are essential tools in scientific research, allowing scientists to perform various experiments, analyze substances, and study biological or chemical processes in a controlled laboratory environment.