cover glass
A student carefully places a cover glass over a drop of water on a microscope slide.
- Noun:
- A small and very thin piece of glass used to cover the specimen on a microscope slide: A "cover glass" is a thin, flat, and usually square or circular piece of glass. Its primary function is to be placed over a specimen (e.g., a drop of liquid or a thin slice of tissue) that has been placed on a microscope slide. This holds the specimen in place, flattens it for clearer viewing, and protects the microscope's objective lens from contact with the sample.
- Noun:
- After placing the sample on the slide, she carefully lowered the cover glass to avoid creating air bubbles.
- The biologist cleaned the cover glass with lens paper before preparing the next slide.
- A standard box of microscope supplies includes slides and cover glasses.
"To apply a cover glass": The act of placing the cover glass onto the specimen.
- The protocol instructs you to apply a cover glass at a 45-degree angle to minimize bubbles.
"Cover glass thickness": A specification important for high-magnification microscopy, as objectives are often corrected for a specific thickness (e.g., No. 1.5).
- For optimal image quality with the 100x oil immersion objective, ensure you use a cover glass of the correct thickness.
Cover slip (n): A complete synonym for "cover glass," more commonly used in everyday laboratory language.
- Please hand me a box of cover slips.
Microscope slide (n): The rectangular piece of glass on which the specimen is placed before being covered by the cover glass.
- Mounting medium (n): A substance (e.g., water, oil, or resin) often used between the specimen and the cover glass to preserve and clarify the sample.
- Cover slip: The most direct and commonly used synonym.
- Microscope cover: A less common but descriptive term.
"To mount a specimen": The complete process of preparing a sample on a slide, which often includes adding a mounting medium and a cover glass.
- The tissue section was mounted in glycerol and sealed under a cover glass.
"To seal a cover glass": To use nail polish, glue, or another sealant around the edges of the cover glass to prevent the sample from drying out or moving.
- For permanent slides, you must seal the cover glass with clear nail polish.
A student carefully places a cover glass over a drop of water on a microscope slide.
- a small and very thin piece of glass used to cover the specimen on a microscope slide