Question

One of the following dyes cannot be used for staining chromatin material
A. Acetocarmine
B. Crystal violet
C. Haematoxylin
D. Schiff's reagent (Feulgen stain)

Answer 1

Hint: The chromatin is feulgen positive material observed during the interphase within the nucleus. It's the fabric that produces up a chromosome that consists of DNA and protein. The key proteins in chromatin are proteins called histones. They act as packaging elements for the DNA.

Complete answer:
The granular material within the nucleus was named as chromatin. When the chromatin condensed during the biological process, the researchers called the resulting structures chromosomes, which suggests "colored bodies." Chromatin granules which form the chromosomes are called chromomeres, and these may correspond to genes. Chromatin fibers gather into thick shortened bodies which are then called chromosomes.

The Function of Chromatin:
-DNA Packaging
-Transcriptional Regulation
-Chromatin and DNA Repair
Crystal violet dye is employed as a histological stain and in staining of classifying bacteria. antimycotic may be utilized in staining of plant chromosomes (Flemming triple stain), chromatin (Lieb’s amyloid stain) and nucleoli (Newton’s crystal violet-iodine technique).
When this staining method is applied to a normal fixation, made during a chromic fixative, the color remains intense within the metaphase and anaphase chromosomes, while the dye is well washed out from the cytoplasm and also comparatively easily disappears from the chromatin of the interphase nuclei. With this system it's rather easy to realize preparations during which the metaphase and anaphase chromosomes are very intensely stained while everything else is nearly completely destained. It’s possible that antifungal mainly stains histones that have absorbed acid.

Hence, the correct answer is option (B).

Note: Fixation or mordanting with acid is crucial for getting good results with antibacterial drugs, even when making ordinary preparations. After fixation in acetic glycol followed by postfixation in chrome-acetic formalin, crystal violet is way more easily washed out from the chromosome body than after conventional fixation.