Question

why are plant and animal specimen ussualy stained with dyes before observing them through a microscope ? name one stain (or dye) used for this purpose?

Answer 1

animal cells and specimens are really small and it is hard to distinguish different parts of them just under the microscope. So they are dyed, as different parts soak different capacity of stains. such as nucleus in a plant cell soaks up the most of the stain while cytoplasm and cell wall don't soak much stain.

one such stain is : methylene blue(cheek cell) (animal cell)