Question

name the stains used to prepare slides like that of onion peel and cheek cell ? why is the use of stain necessary ? do all organisms obtain equally ?

Answer 1

We will use methylene orange, methylene blue,etc as the stains.
We use the stains to observe the nucleus and other cell organelle clearly.
There different types of uses of the stains
The most known and the visible by stains is nucleus

Answer 2

The stain used to perform experiments with onion is iodine.

Iodine easily stains the cell walls of its cells due to the presence of simple carbohydrates. The stain used to perform experiments with cheek cells is methylene blue. The cheek cells easily take of the stain of methylene blue.  

The reason of using stains is necessary as mostly the cells are colourless and transparent or translucent and without stains, they cannot be views distinctly under the microscope. All organisms do not contain or take up stains equally.