When we look at biological cells under a microscope, they’re usually not very colourful. Normally, to visualise them we have to artificially add colour — typically by staining. By doing so, we can see ...

Cells are tiny, so we use microscopes to see their details. A slide is a thin piece of glass used to hold objects which are examined under a microscope. Peel a thin layer of cells from an onion. Place ...