microbiology - taxonomy Flashcards
taxonomy
science of classification
organised into talons
- a group of related organisms
cladistics
approach to biological classification which categorises organisms into clades
clade
group of taxa that are all descended from a common ancestor
grade
group of taxa that share common morphological or physiological traits but excludes sister taxa based on those same traits
7 pillars of life
program
- organised plan of ingredients and kinetics between them
improvisation
- alteration of programme in response to environment
compartmentalisation
- confined to limited volume and isolated from environment
energy
- open metabolising system
regeneration
- compensation for thermodynamic losses
adaptability
- behavioural response part of the programme
seclusion
- chemical control and selectivity
order of taxons
domain - prokarya and eukaryotic
kingdom
phylum - based on body plan
class
order
family
genus - have common ancestor but distinct from each other
species
species
two organisms that can breed and produce viable offspring
biological species concept
groups of actually or potentially interbreeding natural populations
reproductively isolated from other groups
phylogenetic species concept
an irreducible group (cant be split into smaller groups)
members are defended from a common ancestor
all possess a combination of derived traits
plesiomorphy
ancestry trait shared by 2 or more taxa
apomorphy
derived trait unique to a taxon
synapomorphy - if derived trait shared by taxon or daughter taxa
autapomorphy - if derived trait distinguishes it from sister taxa
phylogeny
evolutionary relationships between taxa
phylogenies based on
- morphological characteristics (physical)
- genetic characteristics (DNA)
represented in phylogenetic tree showing common ancestors
paraphyletic group
group has a common ancestor and some descendants
polyphyletic group
does not include a common ancestor (due to errors in phylogeny)
