4.2.2

• phylogenetic classification


  arranges species into groups according to their evolutionary origins and relationships based on how closely related to others species they are and how recently they shared a common ancestor
• phylogenetic tree

  A) A

  B) B

  C) A

  D) B

  E) C

  F) D

  G) E

  H) root

  I) past

  J) present

  
• hierarchy


  smaller groups arranged within larger groups with no overlap between groups
• example of a hierarchy

  biological classification system
• classification system

  A) general

  B) specific

  C) decreasing number of organisms

  D) domain

  E) kingdom

  F) phylum

  G) class

  H) order

  I) family

  J) genus

  K) species

  
• binominal naming system


  naming an organism using its genus and species in Latin
• why use a binomial naming system

  it can be used universally to identify organisms

  it identifies how closely related species are
• writing binomial naming 


  capital letter for Genus

  lowercase letter for species

  underline name
• 5 kingdoms


  prokaryotae

  protoctista

  fungi

  plantae

  Animalia
• prokaryotae


  unicellular

  no membrane bound organelles

  small 70s ribosomes

  free rings of DNA and plasmids

  absorb nutrients or photosynthesize
• protoctista


  unicellular

  nucleus

  membrane bound organelles

  chloroplast

  cilia

  flagella

  photosynthesize or other organisms
• fungi


  uni or multi cellular

  nucleus

  membrane bound organelles

  no chloroplast

  cannot move

  hyphae

  saprotophient

  glycogen stores
• plantae


  multicellular

  nucleus

  membrane bound organelles

  do not move

  photosynthesize

  store starch
• Animalia


  multicellular

  nucleus

  membrane bound organelles

  no chloroplasts

  cilia

  flagella

  muscles to move

  digest nutrients

  glycogen stores
• classification used to be based on

  phenotype and observable characteristics
• what is the problem with phenotypic classification

  members of the same species can look different

  members from different species can look similar
• what stopped phenotypic classification

  genome sequencing and immunology
• DNA base sequencing for classification

  a DNA base sequence for a common gene is compared between individuals and species. the more similar the sequence the closer the relation.
• why do closely related organisms have similar DNA base sequences

  their common ancestor is more recent so there has been less time for mutation to accumulate
• sequencing amino acids for classification

  compared a polypeptide chain sequence that determines the structure and function of a protein. The more similar the closer the related
• why is using amino acids for classification less popular

  the genetic code is degenerate so could DNA code could be different but produce the same amino acid
• domains were added in

  1977 by Carl Woese
• 3 domains


  archaea

  bacteria

  eukaryota
• bacteria and archaea domains feed into which kingdom

  A) prokaryotae

  
• with the new domain system the prokaryotae kingdom can instead be split into

  archaebacteria ( extremophile ) and eubacteria ( common ) kingdoms
• domains split into kingdoms based on

  rRNA

  ribosomes

  cell membrane structure
• evolution history timeline


  proposed by Wallace 1858

  co published theory with Darwin 1858

  origins of species published by Darwin 1859
• evolution


  a change in allele frequency of a population over time due to natural selection
• why was evolution opposed?

  it went against peoples religious beliefs and societal understanding
• evidence for evolution


  fossils

  DNA evidence

  Molecular evidence
• fossils


  formed when the remains or imprints of a dead organism are preserved in rock with minerals replacing the organic matter

  they provide evidence of how a species has changed over time.

  carbon dating can be used to identify what time period they are from
• problem with fossils


  rare

  incomplete timeline

  do not show all organic material
• DNA and molecular evidence

  comparison of a DNA or molecular sequence between organisms can show how closely related species are and when they shared a common ancestor
• types of adaptations


  anatomical

  behavioural

  physiological
• anatomical


  internal or external physical visible features
• behavioural


  how the organism acts
• physiological


  processes within an organism
• convergent evolution


  when organisms from different taxonomical groups develop similar adaptations
• why does convergent evolution occur

  when organisms are all exposed to the same selection pressures in the same way so become more genetically similar
• types of variation


  interspecific

  intraspecific

  continuous

  discontinuous