2.1 Classification and biodiversity Flashcards
What is biological classification said to be?And what does this mean?
Said to be phylogenetic
reflects evolution of an organism by placng organisms into groups according to visible external features
Name the eight taxon groups in increasing degree of similarity
- Domain
- Kingdom
- Phylum
- Class
- Order
- Family
- Genus
- Species
What are the three domains?
- Archaea (bacteria living in hostile environments
- Eubacteria (common bacteria)
- Eukarya (includes plants, animals, fungi and protoctists)
What are the five kingdoms?
- Plantae
- Animalia
- Fungi
- Prokaryotes (bacteria)
- Protoctista
What are kingdoms then sorted into?
a large no. of smaller groups called Phyla - all have a specific thing in common
What is a genus? What can’t they usually do?
a group of organisms w/a large no. of similarities
- usually members of a diff species within a genus are unable to interbreed successfully
Define the term species
consists of a group of individuals w/similar characteristics that can interbreed and produce fertile offspring
What are protoctista?
mainly unicellular eukaryotic microorganisms that don’t form tissues (many are photosynthetic)
What is the binomial system?
created by Carl Linnaeus
universal as helps avoid confusion between different languages
why is the naming system tentative?
may be subject to change as a new species are discovered which don’t neatly fit into the groups currently available
What are the key features of the kingdom Plantae?
- multicellular eukaryotic (autotrophic) organisms that photosynthesise
- reproduce using spores or seeds
- possess cellulose cell walls
What are the key features of the kingdom Animalia?
- multicellular, heterotrophic eukaryotic organisms
- no cell walls
- show nervous coordination
What are the key features of the kingdom Fungi?
- multicellular (moulds) or single celled (yeasts), eukaryotic
- cell wall made of chitin
- they are heterotrophic, being either saprophytic or parasitic
- reproduce using spores (moulds) or by budding (yeast)
What are the key features of the kingdom Prokaryotes?
- microscopic, unicellular organisms including bacteria
- cell wall made of peptidoglycan
- lacks membrane-bound organelles
- ribosomes are smaller than eukaryotes (70s vs 80s)
What are the key features of the kingdom Protoctista?
- includes algae and slime moulds
- some are unicellular and resemble animal cells (Amoeba)
- others have plant like cells
- contain membrane-bound organelles and a nucleus
What kind of evolution are homologous structures evidence of? What are homologous structures? An example?
Divergent evolution
Similar structures evolved to perform different features
Pentadactyl limb - humans=hands bats=wings
What kind of evolution are analogous structures evidence of? What are analogous structures? An example?
Convergent evolution
Same function but a different structure/shape
Bird wings vs butterfly wings
Define behavioural evidence
similar behavioural patterns
Define biochemical evidence
comparison of amino acids of 2 species OR DNA hybridisation/extraction
Define immunological evidence. What does it involve creating?
immunological comparisons of proteins
- involves creating antibodies to one specie’s proteins in a rabbit, which can then be presented to other species’ proteins
Define biodiversity
the no. of species and the no. of individuals of each species in a given environment
What is species richness?
the measure of the no. of different species in a community
What is species evenness?
the no. of organisms within each species
Why does biodiversity increase closer to the equator? But what is also a factor?
increase in light intensity (but water availability is also a factor)
What are the three factor affecting biodiversity?
- Succession (composition of a community changes over time as different species colonise
- Natural Selection
- Human activity (pollution, over-fishing, deforestation…)
Define extinction. What is the normal rate of extinction and what have humans increased this to?
Total loss of a species
1 per 1 mil increased this between 1000 to 100,000 times
Define conservation.
actively planning to protect a species or habitat
Name 6 conservation methods
- CITES
- SSSI and National Parks
- Government agencies and other organisations
- Captive breeding programmes (zoos and safaris)
- Seed banks
- Government legislation
What do CITES do
Ban the sale of an endangered species and their parts of products
What does SSSI and national parks do?
Protect habitats from over-development
What do government agencies and other organisations do?
educated, lobby government, raise awareness and fund conservation projects and monitor change in biodiversity
What do captive breeding programmes do?
breed endangered species in captivity, ensuring limited human contact and then reintroducing species to the wild
What do seed banks do?
carry out research into plant species and their genetic diversity, collect and preserve of all species
What does government legislation do?
pass legislation to protect habitats and species at risk
What is a locus?
a gene’s position on the chromosome
what does a locus show?
polymorphism if it has two or more alleles that cannot be accounted for by mutation alone
Give an example of the proportion of alleles in a whole gene pool and recessive alleles
if we consider a whole gene pool and 98% of all the alleles of a particular gene have the same recessive allele, there is a low biodiversity for that gene
What are some sampling techniques?
mark, release, recapture
kick sampling and simpson’s index
quadrats and transects
What is natural selection?
the gradual process in which inherited characteristics become more or less common in a population, in response to a change in the environment and new selection pressures
What are some new selection pressures?
competition, predation, disease
