2.1 Classification and biodiverity Flashcards
taxonomy
the identification and naming of organisms
classifications
putting items into groups
hierarchey
a system of ranking where smaller groups are nested components of larger groups
hierarchey
a system of ranking where smaller groups are nested components of larger groups
taxon
any group within a system of classification
hierarchey of biological classification:
D, King, Philip, Cried, Out, For, Goodness, sake
doman
kingdom
phylum
class
order
family
genus
species
What are the characteristics of animals?
Multicellular eukaryotes
Nervous coordination
No cell wall
Heterotrophic (consume and digest food)
What are the characteristics of fungi?
Heterotrophic eukaryotes
Chitin cell wall
Reproduce by spores
Most have filaments called hyphae
What are the characteristics of protists?
(simple eukaryotic organisms that are neither plants nor animals or fungi.)
Unicellular
No tissue differentiation
What is an extremophile?
Microbes that are able to exist in extreme conditions of temperature, pH, salinity or pressure
What is the main problem of classifying organisms based on appearance?
Morphological convergence
Different species are subjected to the same selection pressures so develop similar features
Give an example of morphological convergence.
The development of wings in birds and insects
What is an example of divergent evolution?
Pentadactyl limb
Homologous feature - evolved from same structure for different functions
What biochemical techniques can be used to avoid mis-classification due to convergent evolution?
DNA ‘genetic fingerprinting’ - similar banding patterns
Protein sequencing
What is biodiversity?
The number of species (species richness) and the relative number of individuals within each species (species evenness)
What is polymorphism?
The presence of multiple alleles at a locus
What type of adaptations do organisms have?
- Behavioural
- Morphological
- Physiological
How has biodiversity been generated?
Natural selection
How is biodiversity measured at a molecular level?
Analysing base sequences within DNA to look for variations within species
What are the main inaccuracies when counting river invertebrates?
Misidentification
Miscounting in tray
Not all organisms in stream captured
How is biodiversity measured at a genetic level?
Assessing the degree of polymorphism within a population
How is biodiversity measured at species level?
Simpson’s Diversity Index
analogous structures
Have evolved from different structures for the same function
What are the 5 kingdoms?
Prokaryotae
Protoctista
Fungi
Plantae
Animalia
What are the characteristics of prokaryotes?
-No membrane-bound organelles
-No nuclear envelope (circular DNA free in cytoplasm)
-Cell wall does not contain cellulose or chitin
What biochemical techniques can be used to avoid mis-classification due to convergent evolution
DNA ‘genetic fingerprinting’
DNA hybridisation
Protein sequencing - amino acid
DNA sequencing - base
Protein immunology
Why is genetic diversity important?
Diverse gene pool enables a population to adapt more readily to a changing environment
What are the characteristics of plants?
Multicellular eukaryotes
Cell walls made of cellulose
Carry out photosynthesis (autotrophic)
What factors affect biodiversity?
Habitat loss
Invasive species
Pollution
Population growth
Overexploitation
What does phylogenetic mean?
the study of evolutionary relationships among biological entities
Why is classification described as “tentative”?
classification is based on the information available at the time and is subject to change as new information comes to light
what are the 3 domains
Archaea, the Bacteria, and the Eukarya
what is homologous
Homology is the similarity in structure between different organisms based on their descent from a common, evolutionary ancestor.
what does analogus mean
similar or comparable to something else either in general or in some specific detail.
