What is the function of a graduated cylinder?

The function of a graduated cylinder is to accurately measure a volume of liquid, and this is typically expressed in milliliters. This type of laboratory glassware is specifically designed with marked measurements along its side, allowing for precise liquid volume readings. The narrow, tall shape of the graduated cylinder minimizes meniscus distortion, leading to more accurate measurements compared to other containers like beakers or flasks.

While the other options mention tasks related to liquid handling or preparation, they do not focus on the primary purpose of a graduated cylinder. For instance, mixing reagents or preparing solutions can be done in various types of containers, and storing samples for observation is typically not the main use of graduated cylinders. The clarity and accuracy in volume measurement are what set graduated cylinders apart in scientific experiments.