Systematics And Taxonomy

Question 1

Taconomy?

Answer 1

Science of biological classification

Question 2

Three parts of taxonomy?

Answer 2

Classification - arrangement of organisms into groups
Nomenclature - assignment of names to taxa
Identification - determination of taxon to which an isolate belongs

Question 3

Systematics?

Answer 3

Study of organisms with ultimate object of characterizing and arranging them in an orderly manner

Question 4

Stromatolites

Answer 4

Cyanobacteria produce calcium carbonate sheaths and help from fossils

Question 5

What did Carl Woese do?

Answer 5

Theories based on characterization of rRNA sequences. Separated Bacteria and Archaea. 16rDNA molecule

Question 6

16s rDNA

Answer 6

Universal molecule in all bacteria. “Gold standard” for phylogenetic relationships - Ludwig and Schleifer

Question 7

What are two major hypotheses?

Answer 7

Invagination of plasma membrane - ER - mitochondria

Endosymbiotic hypothesis

Question 8

Apomorphy

Answer 8

Derived trait

Question 9

Pleiomorphy/Synapomorphy

Answer 9

Ancestral characteristic

Question 10

Biological species concept

Answer 10

Same species can breed

Question 11

Why can’t we use Biological Species Concept?

Answer 11

Dogs/wolves can reproduce

Bacteria are asexual

Question 12

Strain

Answer 12

Population that is distinguishable from others within that lineage via some set of features

Question 13

What are three major strains?

Answer 13

Biovars
Morphovars
Serovars

Question 14

Biovars

Answer 14

Differ biochemically and physiologically

Question 15

Morphovars

Answer 15

Differ morphologically

Question 16

Serovars

Answer 16

Differ in antigenic properties

Question 17

Type strains/species

Answer 17

First strain studied

Most fully characterized

Question 18

Binomial system of nomenclature

Answer 18

Linnaeus

Question 19

Classification system Linnaeus proposed

Answer 19

Phenetically

Phylogenetically

Question 20

Phenetically

Answer 20

Grouped together based on overall similarity

Question 21

Phylogenetically

Answer 21

Grouped based on probable evolutionary relationships

Question 22

Major Taxonomical Characteristics

Answer 22

Classical

Molecular

Question 23

Classical characteristics?

Answer 23

Morphological - doesn’t apply to bacteria
Physiological and metabolic - based on biochemical pathways, does not distinguish bacteria, great for pathogens
Ecological
Genetic analysis

Question 24

Molecular Characteristics?

Answer 24

Comparison of proteins
Nucleic acid base composition (G/C content)
Nucleic acid hybridization
Nucleic acid sequencing

Question 25

Specificity for nucleic acid hybridization?

Answer 25

The temperature needed to break apart the bonds and the temperature that allows the strands to reanneal. Organisms that have more in common should have a different temperature, should be able to reanneal at higher temperatures.

Question 26

Molecular chronometers

Answer 26

Nucleic acids or proteins used as clocks to measure amounts of evolutionary change over time

Question 27

Molecular chronometer assumptions

Answer 27

Sequences gradually change over time
Changes are selectively neutral and random
Amount of change increases linearly with time

Question 28

What are disadvantages of molecular chronometers?

Answer 28

Not all genes are under the same evolutionary or selective pressures

Question 29

Nodes

Answer 29

Taxonomic units (species/genes)

Question 30

Terminal nodes

Answer 30

Living organism

Question 31

Polyphasic Taxonomy

Answer 31

Use of all possible data to determine phylogeny

Question 32

The major divisions of life

Answer 32

Bacteria
Archaea
Eucarya