Simple Stain Flashcards
1
Q
Simple Stain
A
Uses only one stain
2
Q
Most Common Stains for Simple Stain
A
Methylene blue and crystal violet
3
Q
Two types of simple stains
A
Basic (Positive) and Acidic (Negative)
4
Q
Basic Stain
A
- Positive Stain
- Colors actual bacteria
- Bacteria are negatively charged
- Stain contains chromophores
- Basic stain contains cations
- Stain is attracted to bacteria
- Requires heat fixation: possible distortion of cells
5
Q
Charge of bacteria
A
Slightly negative
6
Q
Chromophores
A
Color-bearing ions
7
Q
Acidic Stain
A
- Negative Stain
- Colors background
- Bacteria are negatively charged
- Stain contains chromophores
- Acidic stain contains anions
- Stain is repelled from bacteria
- Does not require heat fixation: no distortion of cell shape or size
- Stain used: Nigrosin stain
