classifications of bacteria

Question 1

how many approaches of classification/taxonomy are there? Namely

Answer 1

Numerical, Phylogenetic, Polyphasic,

Question 2

A similarity matrix that helps to group similar strains together is called?

Answer 2

Dendrogram

Question 3

Phylogenetic approach compares DNA of one organism to another using a method called

Answer 3

Nucleic acid / DNA hybridization

Question 4

In which approach of classification are bacteria sharing similar morphology,biochemistry and susceptibility to drugs are grouped together

Answer 4

neumerical/computer or phenotypic approach

Question 5

In numerical approach you calculate

Answer 5

coefficient/percentage of similarity

Question 6

In phylogentic approach you calculate

Answer 6

percentage of divergence or DNA relatedness

Question 7

who proposed numeric approach

Answer 7

edwards and ewing (on the study of enterobacteriaceae)

Question 8

Factors affecting DNA relatedness

Answer 8

genome size
guanine-plus- cytosine (G+C) content
conditions optimal for DNA reassociation
conditions supraoptimal for DNA reassociation
thermal stability

Question 9

how much do True bacterial DNAs weigh?

Answer 9

1-8x10 to the power of 9 MWs

Question 10

For instance which species were differentiated using their genome size?

Answer 10

Legionella pneumophila Vs Bartonella (Rickettsia) quintana

Question 11

Range of G+C content in a bacterial DNA

Answer 11

25-75%

Question 12

True or false

Two strains with higher G+C Content percentage are always in the same species

Answer 12

False

G+C content specific but not exclusive OR it rules out but does not always rule in

Question 13

optimal temperature for DNA reassociation

Answer 13

25-30 degree Celsius below denaturation temperature

Question 14

True or False

Bacterias have DNA relatedness compared to other species

Answer 14

True

70-100% related

Question 15

True or False

thermal stability and nucleotide pairing have a linear association

Answer 15

True

1% nucleotide unpairing decreases thermal stability of the DNA by 1%

Question 16

DNA relatedness test at supraoptimal conditions incubate DNAs at what temperature

Answer 16

10-15% below denaturation point (higher than optimal temperature therefore more specific)

Question 17

true or false

according to DNA relatedness studies E.coli and shigella should be grouped together

Answer 17

True( they are not grouped together because of the nomenclature confusion it would create)

Question 18

the practical approach to bacterial taxonomy should be ——

Answer 18

Polyphasic

numeric followed by phylogenetic followed by reexamination of biochemical characteristics of related groups

Question 19

Morphologic characterstics include–?

Answer 19

Gram reaction
Acid fast reaction
motility
shape
spores, capsules, inclusion bodies