Lec. 17: Microbial Classification

Question 1

The science of biological classification is

Answer 1

taxonomy

Question 2

What are the two reasons that the biological concept of species is not readily applicable to microbes?

Answer 2

1- Their genomes change rapidly;

2- Their frequent use of asexual reproduction

Question 3

What is the most basic (narrowest) taxonomic unit?

Answer 3

species

Question 4

How does the concept of species differ between eukaryotes and prokaryotes?

Answer 4

• A prokaryotic species is a population of cells with similar characteristics
• Prokaryotes do not perform cell division by sexual conjugation, therefore reproduction is not always species-specific
• A eukaryotic species are grouped together based on the ability to exchange genes and breeding

Question 5

What is a strain in microbiology?

Answer 5

the population of bacteria that originated from a single organism

Question 6

What is a genus?

Answer 6

A principal taxonomic category that ranks above species and below family, and is denoted by a capitalized Latin name.

Question 7

Describe binomial nomenclature.

Answer 7

A the two-word naming system for identifying organisms by genus and the specific epithet

Question 8

Who developed binomial nomenclature?

Answer 8

Carolus Linnaeus

Question 9

How are the names formatted in binomial nomenclature?

Answer 9

The genus part of the name is always capitalized; it is followed by the specific epithet name, which is not capitalized. Both names are italicized.

Question 10

Who makes the name “official” in binomial nomenclature?

Answer 10

International Code of Nomenclature of Bacteria

Question 11

What is the mnemonic for the taxonomic levels?

Answer 11

“Dear King Phillip Came Over For Good Soup”

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

Question 12

What are the examples of morphology?

Answer 12

spheres (coccus);
ended cylinders (bacillus);
helically twisted cylinders (spirochetes)
vibrio (curved rod)

Question 13

What are the examples of differential staining?

Answer 13

Gram staining;
acid-fast staining;
endospore staining;
flagella staining; 
capsule staining

Question 14

Examples of biochemical tests?

Answer 14

Mannitol Salt Agar
Catalase Test
Blood Agar Test
Oxidase Test
MacConkey Agar

Question 15

What are examples of serology?

Answer 15

Precipitation test
Western blot test
Immunofluorescence test

Question 16

What is a biochemical test?

Answer 16

check metabolic properties , catalase test

Question 17

What is serology?

Answer 17

Identification through antibodies

Question 18

What is phage typing?

Answer 18

A method of identifying bacteria using specific strains of bacteriophages.

Question 19

What is phylogeny?

Answer 19

Classification based on evolutionary relationships, use ribosomal RNA to look at changes (change very slowly)

Question 20

molecular chronometer

Answer 20

Nucleic acids or proteins used as “clocks” to measure the amount of evolutionary change over time; their rates of mutation are constant and can be used to construct phylogenetic trees.

Example: ubiquitin: a small regulatory protein found in most tissues of eukaryotic organisms

Question 21

phylogenetic tree

Answer 21

diagrams changes over time

Question 22

Provide all the taxonomic levels of your microbe of choice as described in your first assignment in Microbial Ecosystems.

Answer 22

Acidiphilium acidophilum
Domain:        Bacteria
Kingdom:      Eubacteria
Phylum:         Proteobacteria
Class:            Alphaproteobacteria
Order:           Rhodospirillales
Family:          Acetobacteraceae
Genus:          Acidiphilium
Species:        acidophilum