4.2 3 domains and phylogeny Flashcards
what happens to classification systems as we learn more about organisms?
they change
what changes as organisms evolve?
their internal and external features as well as their DNA
scientists can discover evolutionary relationships by comparing similarities in what?
organisms DNA and proteins
what domain system did Carl Woese develop?
the 3 domain system
in the 3 domain system organisms are grouped using differences in what?
sequences of nucleotides in cells rRNA
cell membrane lipid structure
sensitivity to antibiotics
from the 60s organisms have been classified in which system?
5 kingdom system
in the 5 kingdom system what are organism groups based on?
common physical characteristics
what are the 3 domains in the 3 domain system?
archaea
bacteria
eukarya
how many kingdoms are in the 3 domain system?
6
what does the eukarya domain consist of?
80s ribosomes
RNA polymerase contains12 proteins
what does the archara domain consist of?
70s ribosomes
RNA polymerase contains- 10 proteins similar to eukaryotic ribosomes
what does the bacteria domain consist of?
70s ribosomes
RNA polymerase contains 5 proteins
archaea domain contains which kingdom?
archaebacteria kingdom
the bacteria domain contains which kingdom?
eubacteria kingdom
the eukarya domain contains which kingdoms?
Protista
fungi
plantae
animalia
what are archaebacteria?
ancient bacteria
where can archaebacteria live? give examples.
extreme environments
e.g. hot thermal conditions, acidic environments, anaerobic conditions
give an example of archaebacteria surviving in extreme environments:
methanogens in sewage treatment plants (anaerobic conditions)
where are eubacteria found?
found in all environments
(Phylogeny) what is phylogeny the study of?
How closely different species are related - the evolutionary relationship between them
(Phylogeny) phylogeny is used as a basis for what?
Classification
(Phylogeny) what is a phylogeny tree?
Diagram used to represent evolutionary relationships between organisms
(Phylogeny) the closer related the species the closer they appear where?
On the tree
(Phylogeny) what are found at the base of the tree and what are found at the tips?
Base - earliest species
Tips - most recent species
(Phylogeny) trees are produced by looking at differences in what?
Species physical characteristics and genetic makeup
(Phylogeny) the set of organisms in the tree is known as what?
A taxa
(Phylogeny) the tips of the tree represent group of descendant what?
Taxa- often species
(Phylogeny) noses of the tree represent what?
Common ancestors of the descendants
(Phylogeny) two descendants splitting from the same group are known as what?
Sister groups
(Phylogeny) what is the outgroup?
Taxon outside the group of interest, less closely related
(Phylogeny) what does phylogeny consider in classifying animals?
Their genes
Give an example of wrong classification based on physical appearance:
Dolphins classified as fish when they are mammals
(Phylogeny) phylogenic classification is useful as it takes into account what?
Evolutionary relationships not visible by physical characteristics
(Phylogeny) advantage - groups shown according to what rather than being hierarchical?
Shown according to evolutionary position so their evolutionary relationships can be compared
(Phylogeny) advantage - classification forms a continuous tree so organisms don’t have to be forced into what?
Groups they don’t fit in
