Question

During staining, chromosomes get stained with
(A) Eosine
(B) Borax carmine
(C) Acetocarmine
(D) Safranin

Answer 1

Staining is the process of adding the stain and the dye to the microscopic objects in order to enhance contrast and to highlight the structures etc. This is mainly used for viewing microorganisms like bacteria, virus etc. and the cell organelles.

Complete answer:
(A) Eosine:-These substances are used for the staining of the cytoplasm of the cell. Since these stains are acidic in nature, they stain the basic cell organelles.
(B) Borax carmine:-It is the combination of both borax, carmine and the water. These are called the nuclear stain which is used to stain the nucleus. This is also effective in staining the cytoplasm of the cell.
(C) Acetocarmine:-It consists of the saturated solution of the carmine in the 45% acetic acid. It is used to study the stages of cell division in the chromosomes like mitosis or meiosis. Hence it is used in the staining of the unfixed chromosomes.
(D) Safranin:-This safranin is used in the field of histology and cytology. It is counterstain in nature.
From all the explanations above, it is clear that acetocarmine is used to stain the chromosomes.

Thus, the option (C) is the correct answer.

Note: The staining is of two types as positive staining and the negative staining. In the positive staining the dark object formed on the lighter background where the negative staining produces the lighter object on the darker background.