the process of grouping species into related "families" that share something in common. The basis that classifications can be made can be either artificial or phylogenic.
what does artificial classification use?
the similarities and differences in given features (eg: no. of legs, shape of leaf).
what are the two classification methods?
artificial or phylogenic.
which is the better classification method?
phylogenic.
what does phylogenic classification do?
takes the evolutionary relationship into account, underpinned by evolutionary relationships and links and also classifies species into groups where shared features have been passed down from common ancestors.
what does phylogenic classification make use of?
a clear hierarchy where species are grouped, each level is grouped into broader groups above, while maintaining evolutionary relationships of some kind.
what is an important part of identifying evolutionary links that form phylogenic classification systems?
homologous characteristics.
what are homologous characteristics?
similarities between limbs that reveal their shared evolutionary origin despite their different functions.
what is a taxon?
A taxon is a group of organisms that are classified together based on shared characteristics.
what is the order top to bottom of the taxa of the classification system?
domain (dont)
kingdom (kill)
phylum (penguins)
class (cause)
order (otters)
family (feel)
genus (generous)
species (soon)
which is the most specific taxon?
species.
what is the most general taxon?
domain.
what are the 3 domains?
bacteria, archaea and eukarya.
describe the bacteria domain.
single celled prokaryotes. Don't have membrane bound organelle and they possess the sampler 70S ribosomes. DNA is a single strand. Cell walls made of murein.
describe the archaea domain.
for a long time was in the bacteria domain but was discovered their DNA was more similar to eukaryotes. Single celled, but their membranes are more complex. Comprised of fatty acids and no murein. Their RNA polymerase is more complex than that of bacteria.
describe the eukarya domain.
comprised of eukaryotic cells which are less primitive, contains membrane bound organelle, larger 80S ribosomes and complex membranes and cell walls. Can be single celled or complex multi-celled organisms.
what is the idea behind the classifications and the hierarchal order?
phylogeny.
what is phylogeny?
the idea that each taxa has some evolutionary relationship or link to another and these relationships exist to different degrees. Species are evolutionary and genetically related.