Question

WHY DO WE STAIN CELLS GREW WHILE OBSERVING under microscope? List commonly used stains.

Answer 1

staining is a technique used to enable better visualization of cells and cell parts under the microscope. By using different stains, a nucleus or a cell wall are easier to view. Most stains can be used on non-living (fixed) cells, while only some types of stain can be used on living cells.
Iodine: Stains carbohydrates in plant and animal specimens brown or blue- black.Stains glycogen red.
Methylene blue: Stains acidic cell parts (like nucleus) blue. Use on animal, bacteria and blood specimens. Can be used as a substitute for Janis B green.
Eosin Y: Stains alkaline cell parts (like cytoplasm) pink. Use on plants,animals and blood. Can be used as a substitute for Congo Red and Carmine.
Safranin : Mainly used for sections of plant tissues, stains red
Toluidene blue: Stains acidic cell parts (like nucleus) dark blue. Good to show mitosis in plant cells.
Wright’s stain: Stains red blood cells pink/red.
Leishman’s stain: Stains nucleus of WBC blue and blood cells pink
Crystal Violet: Stains bacteria purple
Aceto-orcein: Biological stain for chromosomes and connective tissue.
Sudan III: Biological stain used as a lipid indicator.

Answer 2

We use stains to make the cells visible because most of the cells are almost invisible. So, If the cells are invisible it will be hard to study them. Some commonly used stains are:-
For plant cell:-
Safranin
Acetocarmin
Iodine solution
For animal cell:-
Methylene blue
Leishmann stain
For bacteria:-
Crystal Violet
Gram stain

We use different stains for bacteria and animal cell because their cell wall areas made up of different chemicals.

Hope this helps!