Exercise 10: Capsules Flashcards
1
Q
What are most bacterial capsules made of?
A
- of polysaccharides
- some composed of proteins or protein-carbohydrate combinations
2
Q
What are nutrient conditions that could cause the formation of capsules?
A
- media rich in sugars and low in nitrogen
3
Q
Capsules serve what functions?
A
- protects the cell from desiccation (drying)
- protects the cell from phagocytosis ( being enguled by white blood cells)
- allow organisms to stick to surfaces and each other. Prevents organisms from being washed away
4
Q
What the best way to stain capusles?
A
by staining the BACKGROUND and the CELL
5
Q
What is the negative stain used to stain the background?
A
- congo red
6
Q
If the pH is below 3.0 with congo red what will the stain appear? above pH 5.2?
A
blue, red
7
Q
What’s the positive stain used to stain the cells?
A
Maneval’s stain
8
Q
Do you heat fix capsules?
A
yes but you pass through the flame just ONCE
9
Q
Water functions to what?
A
decolorize the cell
