Question

comparing stains
assess the following descriptions, and classify them according to their respective staining type.
minimizes shrinkage and distortion of cells
cells repel stain and appear colorless
capsule stain with nigrosin
useful to quickly determine cell size and shape
used to detect mycobacterium tuberculosis in sputum samples
uses a single dye
uses primary dye and counterstain
negative
differential
simple

Explanation:

• Negative Staining:
• Cells repel stain (so appear colorless against stained background), capsule stain with nigrosin (nigrosin is negative stain, stains background, capsule/cells colorless).
• Differential Staining:
• Used to detect Mycobacterium tuberculosis (e.g., acid - fast stain, differential), uses primary dye and counterstain (differential stains like Gram or acid - fast use multiple dyes to differentiate), minimizes shrinkage/distortion (some differential stains preserve cell structure well).
• Simple Staining:
• Uses a single dye (defining feature of simple stain), useful to quickly determine cell size and shape (simple stains provide basic cell morphology info).

Answer:

• Negative: cells repel stain and appear colorless; capsule stain with nigrosin
• Differential: minimizes shrinkage and distortion of cells; used to detect Mycobacterium tuberculosis in sputum samples; uses primary dye and counterstain
• Simple: useful to quickly determine cell size and shape; uses a single dye