c2.1 - biodiversity + classifications Flashcards
define classification
process of naming + organising organisms into groups based on characteristics + evolutionary history
can classification of organisms change
yes
changes as new info becomes available
name the 7 groups in hierarchy of taxons, largest y to smallest
kingdom
phylum
class
order
family
genus
species
what’s the 5 kingdom classification system
classification of organisms into 5 major kingdoms:
animalia, fungi, plantae, prokaryotae, protoctista
what’s the 3 domain classification system
method of classification where organisms categorised into 3 groups:
arcane, bacteria, eukarya
how was the 3 domain system developed
- by analysing molecular differences between organisms to determine evolutionary relationships
- evidence showed the kingdom ‘prokaryotae’ could be divided in 2 groups, all other organisms are eukaryotes
what do organisms in same domain have in common
organisms in same domain share distinctive pattern of ribosomal RNA
what is bacteria
- one of 3 domains
- consists of ‘true’ bacteria
- also known as eubacteria
what is archaea
- one of 3 domains
- made o primitive bacteria existing in extreme environments, e.g: extremophile prokaryotes
- also known as archaebacteria
what is eukarya
- one of 3 domains
- consists of all eukaryotic organisms
outline features of kingdom prokaryotae
- unicellular prokaryotes
- lack true nucleus + membrane bound organelles
- rigid cell wall
outline features of kingdom plantae
- multicellular eukaryotes
- photoautotrophs
- cellulose cell walls
outline features of kingdom animalia
- multicellular eukaryotes
- no cell wall
- heterotrophic
- nervous coordination
outline features of kingdom fungi
- eukaryotes
- heterotrophic
- chitin cell walls
- grow by producing branching filaments, hyphae
- asexual reproduction via spores
outline features of kingdom protoctista
- mainly unicellular eukaryotes
- no differentiation into tissues
how are diff types of evidence used in classification
observations (e.g: fossils) - organisms grouped based on similar physical characteristics
biochemical methods (e.g: DNA genetic fingerprinting)
what is DNA profiling
- method of determine characteristics of individuals DNA
- percentage of DNA or proteins shared tween species used to estimate relatedness
advantage of using biochemical methods of classification
reduce mistakes made from observing physical features alone (due to morphological convergence)
compare homologous + analogous features
homologous - evolved from same structure for different functions, indicating common ancestor
analogous - structures evolved independently for same function
example of homologous feature
pendactyl limb (found in mammals, birds, + reptiles)
example of analogous feature
wings of birds + insects
define species
group of organsims that can interbreed to produce fertile offspring
2 components of binomial name
generic name - genus to which organism belongs
specific name - species organism belongs too
advantage of binomial naming system
universal; is the same everywhere in the world
define biodiversity
- number + variety of living organisms in given region
- affected by environmental, genetic, + human factors
what mechanism has generated biodiversity
natural selection
when measuring biodiversity of habitat, what must ecologists consider
- species richness
- species evenness
define species richness
number of diff species found within an area
define species evenness
number of individuals of each species living together in a community
how can biodiversity in habitats be assessed
using simpsons diversity index
what’s simpsons diversity index
- measurement of diversity that considers both species richness and+ evennness
- value between 0 + 1 found
- greater value = greater biodiversity
how is genetic biodiversity calaculated within species
proportion of polymorphic gene loci = number of polymorphic gene loci/total number of loci
what is polymorphism
presence of different phenotypes among members of a single species
how can biodiversity be assessed at molecular level
using DNA fingerprinting + sequencing
what is DNA sequencing
determining entire DNA nucleotide base sequence of organism
how is DNA sequencing used to measure biodiversity
comparisons between members of same species can identify variation in base sequences + then estimate genetic biodiversity
what’s an adaptation
feature of organism that increases chance of survival in its environment
describe the 3 types of adaptation
anatomical - changes to physical features
physiological - changes to bodily processes
behavioural - changes to action
