Why are plant and animal specimens usually stained with dyes before observing them through a microscape ? Name one stain (or dye) used for this purpose.

The various parts of the cell are colorless and hence, difficult to distinguish. So, various stains are used to colour the parts of the cell to study the detailed structure through a microscope.

The dyes (stains ) which are used in the study of cell structure are methylene blue, dilute iodine solution, etc.