Infection Case Study Flashcards
1
Q
Describe the purposes of the following in the Gram stain
- Crystal violet
- Gram stain
- Safranin
- Ethyl alcohol
A
- CRYSTAL VIOLET - Primary dye
- Gram’s iodine - mordant
- Safranin - counterstain
- Ethyl alcohol - decolouriser
2
Q
Where is peptidoglycan synthesised and what are they made up of?
A
Cytoplasm
- Cross-linked sugars
3
Q
What is the purpose of the pilus?
A
- Allows bacterial adherence to surfaces
4
Q
How will a Gram positive and negative bacteria appear under a microscope?
A
- GRAM POSITIVE - Purple
- GRAM NEGATIVE - Pink
5
Q
What is the lipopolysaccharide layer also known as?
A
ENDOTOXIN
6
Q
What does it indicate if a catalase test comes up as:
- POSITIVE
- NEGATIVE
A
- POSITIVE - Staphylococcus, E.coli , Listeria, Corynebacterium diphtheriae, Pseudomonas, Mycobacterium tuberculosis
- NEGATIVE - Streptococcus, Enterococcus
7
Q
What level oxygen does microaerophilic bacteria grow well at?
A
5%
8
Q
Give examples of the following
- Alpha - haemolytic bacteria
- Gamma - haemolytic bacteria
A
- Strep infections
- GAMMA - non - haemolytic - e.g Staphylococcus
