Which item is described as a rack for holding up lab equipment when not in use, or for observation?

• A. Peg Rack
• B. Microcentrifuge Tube Rack
• C. Pipette-Aids
• D. Petri Dish

Answer: (B)

Keeping small laboratory vessels organized and readily observable when they’re not in use is what a microcentrifuge tube rack is designed for. It provides a grid of slots sized to hold tiny tubes upright, keeping contents visible, preventing spills, and making it easy to grab a tube during an experiment. This upright storage also helps with drying and inspection between steps. A peg rack serves a different purpose, often for hanging broader items or glassware on pegs and isn’t specifically sized for tiny microcentrifuge tubes. Pipette-aids are tools for transferring liquids, not storage racks, and a Petri dish is a shallow container used for growing cultures, not for holding tubes.