Bacterial taxonomy Flashcards
1
Q
What is phylogeny?
A
- Measures the evolutionary relationships between organisms
2
Q
What is the basis of phylogeny
A
- all living things have genes which mutate randomly (base changes) at low frequency
- All progeny will carry the mutation (base change)
- Organisms differing by a few DNA base changes have diverged more recently in evolutionary time than organisms that differ by more basis
3
Q
In phylogeny what does the branch lengths represent
A
- evolutionary distances
4
Q
In phylogeny what does the internal nodes represent
A
- ancestors
5
Q
In phylogeny what does the external nodes represent
A
- existing strains
6
Q
What are the steps in Taxonomic classification of microbes
A
- Classification
- Nomenclature
- Identification
7
Q
What is genotypic
A
- Classification on the basis of genetic similarities
8
Q
What is phenotypic
A
- physical, structural or metabolic features
9
Q
what is chemotaxonomic
A
- phenotypic classification which measures degree of similarity of biochemical composition of organisms
10
Q
What is Taxonomy
A
- Classification based on shared characteristics (phenetic; overall similarity)
11
Q
What is the taxonomy order
A
- Kingdom
- Phylum
- Class
- Order
- Family
- Genus
- Species
12
Q
What are the similarities of Bacteria and Archaea
A
- share the same shape, size and microscopic appearance
- Differentiation difficult with just a microscope
- Like bacteria, archaea multiply by binary fission and if motile move primarily by means of flagella
13
Q
What are the differences of Bacteria and Archaea
A
- Despite morphological similarities Archaea are more angular / square-shaped than bacteria
- Archaea do not have peptidoglycan, some have no cell wall, some may have protein S-layers, polysaccharide walls and pseudopeptidoglycan
-Archaea genes are more similar to eukaryotes than bacteria - Different 70S ribosome and more complex RNA polymerase
14
Q
A
