What is the purpose of staining samples in light & electron microscopy?

answer! so much! (gcse biology)

Cell stains are used to make samples more visible under the microscope. This is most especially useful for clear or transparent cells and to view cellular components well. With certain differential stains, we can also opt to only view specific parts such as cell walls and nucleus. This is also most helpful in identifying certain species under the microscope.

The purpose of staining samples is to enhance visualization under light and electron microscopy. To highlight also metabolic processes or to differentiate between live and dead in a samples. To determine as well the biomass in an environment of interest. Staining Technique can be used on either living or non-living. 

Ecological footprint is determined by measuring carbon dioxide emissions for a given region.