MT2 > Classification of Infectious Agents Flashcards
Define Taxonomy.
The science of classifying organisms.
Define Phylogeny (systematics).
The study of the evolutionary history of organisms.
Who came up with the binomial naming convention we use today? When?
Carl Linnaeus in 1735.
What were the two original kingdoms identified by Linnaeus?
Plantae and Animalia.
What domains were eventually proposed by Woese in 1978 and universally adopted?
Eukarya, Archaea, Bacteria.
Which domains of organisms have membrane lipids which are composed of straight carbon chains attached to glycerol by an ester linkage?
Bacteria and Eukarya.
Which domains of organisms have membrane lipids which are composed of branched carbon chains attached to glycerol by an ether linkage?
Archaea.
What is the purpose of a phylogenetic tree?
To group organisms according to their evolution from a common ancestor.
With regards to prokaryotic species, what is a culture?
A colony of bacteria grown in laboratory media.
With regards to prokaryotic species, what is a clone?
A population of cells derived from a single parent cell.
With regards to prokaryotic species, what is a strain?
Within a clone, a group of genetically different cells (may have diverged though mutation).
What are the common characteristics of Protista?
A catchall kingdom for variety of autotrophic and heterotrophic organisms.
What are the common characteristics of Fungi?
Chemoheterotrophic, unicellular or multicellular, cell wall of chitin, develop spores.
What are the common characteristics of Plantae?
Multicellular, cellulose cell walls, undergo photosynthesis.
What are the common characteristics of Animalia?
Multicellular, no cell walls, chemoheterotrophic.
What is a “viral species”?
Not a part of any domain, not composed of cells, non-living. A species consists of viruses with similar characteristics sharing an ecological niche.
What differentiates classification and identification?
Classification: placing organisms in groups of related species
Identification: matching an unknown organism to a list of known organisms
What information does Bergey’s Manual of Determinative Bacteriology provide?
Identification schemes for identifying bacteria and archaea.
What information does the Approved Lists of Bacterial Names provide?
It lists bacterial species of known classification.
What 3 major approaches can be used to identify microorganisms?
- Differentiate by morphology
- Differential staining
- Biochemical tests
Under what circumstance should differential staining not be used to identify a microorganism?
When trying to identify a bacteria without a cell wall.
What is meant by a “rapid identification method”?
A test which combines several biochemical tests into one, streamlining the identification process.
Define “serology”.
The science that studies serum and immune responses in serum.
What is the purpose of an antiserum? How does it work?
To identify an unknown bacterium by testing it in a solution of known antibodies.
