Microbial World Flashcards
What are some of the possible consequences of bacterial adherence?
- Activation of the innate and/or adaptive immunity
- Uptake into the cell in a double membrane compartment
- Cytoskeletal rearrangment and entry into the host via the formation of a specialized lesion
What are some important features in defining a bacteria?
Metabolism: test by measuring growth on a particular medium and/or the ability to react with an indicator chemical in the medium.
Requirement for oxygen: test by measuring growth in oxygen.
Sensitivity to antibiotics: test by measuring growth in the presence of antibiotics.
Gram staining: test by performing the Gram stain.
Morphology: test by examining colony morphology and light microscope appearance.
The ability to colonize the human host is:
A. A broad characteristic shared by most bacteria that accounts for their evolutionary success.
B. Present in only a small subset of bacteria and requires significant specialization.
C. A primary difference between prokaryotes and all other organisms
D. Revealed by tests such as the Gram stain and indicator media.
B. Present in only a small subset of bacteria and requires significant specialization.
To identify the bacterium in a clinical isolate, the technician will usually:
A. Perform at least a partial DNA sequence analysis.
B. Grow the bacterium on a variety of indicator media that reveal certain physiological attributes.
C. Attempt to place the unknown organism on a taxonomic tree.
D. Identify the niche that the organism prefers.
B. Grow the bacterium on a variety of indicator media that reveal certain physiological attributes.
How are the microbiota related to infection?
The microbiota are especially important in preventing bacterial infection. The microbiota and the immune system influence each other.
What are the steps that bacteria go through to cause disease?
EXPOSURE to pathogens ADHERENCE to skin or mucosa INVASION though epithelium COLONIZATION and GROWTH production of virulence factors TOXICITY or SPREAD **DISEASE**
