Classification Flashcards
How did the development of life on earth occur?
Through tectonic plate movement and mass extinctions
What are the types of tectonic plate movement?
Divergent (away from eachother), convergent (one under the other) and Transform (sliding past eachother)
What is a mass extinction?
Many species go extinct in short time frame affecting wide range of habitats and species.
What is background extinction?
10-20% species extinct per million years
What is mass extinction event?
More than 50-70% of all species dissapeared, due to major environmental changes and opportunities for new species to form.
What are some causes of mass extinction?
Tectonic shift, volcanic activity and meteorites
How long does it take for recovery of a mass extinction?
5-10 million years which allows increase in diversity
What are the 5 major extinction events?
End Ordovician, End Devonian, End Permian, End Triassic and End Cretaceous
Where did the evolution of classification begin primarily with?
Carl Linnaeus introduced standardised binomial naming, introduced standard of class, order, genus, species and considered the Father of taxonomy. It began in 1753-1758
What did Darwin observe?
Adaptation to environment and origin of new species closely related processes that explains lifes unity and diversity.
How can homology be explained?
Descent with modification
What is natural selection?
variations in genotype that increase an organisms chances of survival and procreation are preserved and multiplied from generation to generation at expense of less advantageous ones
What are the causes of natural selection?
Differences in survival, fertility, rate of development and mating success. ‘survival of the fittest’
What is artificial selection?
human have modified species over many generations, selecting and breeding individuals that possess desired traits.
Who does natural selection impact on and what is the big picture?
It impacts on individuals however is apparent in a population of organisms over time
What is binomial nomenclature?
System of naming a species using 2 names, the genus and species (sometimes subspecies) which make up scientific name of species.
How is does development of new species occur?
Allopatric speciation, sympatric speciation, adaptive radiation and artificial speciation
What is allopatric speciation?
It is habitat isolation, geographically isolated subpopulations
What is sympatric speciation?
It is not isolated habitat, geographically overlapping subpopulations (heteropatric)
What is adaptive radiation?
Many diversely adapted species develop from common ancestors after being introduced to various new environmental changes
What is taxonomy?
The study of classification of organisms based on similarities/differences
What is phylogeny?
Study of evolutionary development of organisms and relationships between them
What is a phylogenetic tree?
Represents evolutionary relationships
What is cladistics?
Analysis of how species may be grouped
What are phylograms?
Branches reflect in number of changes in lineage of phylogenetic tree
What is an ultrametric tree?
Phylograms against actual time
What is systematics?
The study of evolutionary relationships that is made up of taxonomy and phylogeny
What does the tree of life consist of?
Biota (life), 2 empires, 3 domains, 5-6 kingdoms and 36 phyla (9 of which still exist), class, order, family, genus and species
What are the 2 empires?
Prokaryotes and Eukaryotes
What are the 3 domains?
Archaea, Bacteria and Eukarya
What are the 6 kingdoms?
Bacteria, Archae, protista, plantae, fungi and animalia
What are the most well known phylas?
Mollusca, Porifera, Cnidaria, Platyhelminthes, Nematoda, Annelida, Arthropoda, Echinodermata and Chordata
What is protista?
Eukaryotes (not animals, plants or fungi). Protozoa and Chromatista
What are the characteristics of protista?
Can be unicellular, multicellular or colonial. Mixotrophs, photoautotrophs or heterotrophs. Sexual, asexual or both and its physical form has adaptations
What are the 4 main groups of protista?
Excavata, ‘Sar’ clade, Archaeplastida and Unikonta
What are the 3 main groups of excavata?
Parabasalids (modifies mitochondira, anaerobic), Diplomonods (modified mitochondria, mostly parasites) and Euglenozoans (have flagella)
What are the components of the ‘SAR’ clade with examples?
Stramenopiles (diatoms, golden algae, brown algae), Alveolates (dinoflagelletes, ciliates) and Rhizarians (amoebas, forams and cercozoans)
What are some examples of Archaeplastida?
Red algae, Green algae and land plants
What are some examples of Unikonta?
Nucleariids (feed on algae/bacteria and unicellular protists), Choanoflagelletes, Amoebazoans (slime moulds, spore dispersal)
What are the characteristics of Fungi?
Heterotrophs via absorption, multinucleated cells enclosed in cells with cell wall, saprobic (obtain energy by decomposing dead and dying organisms-decomposers) and mutalists/parasites.
What is the structure of fungi?
Multicellular filaments or single cells (yeast), multicellular filaments (hyphae), have chitin walls. Hyphae form interwoven mass for max feeding efficiency (mycelium)
What is the nutrition of fungi?
They are heterotrophs, symbiosis between fungi/plants (mycorrhizae), ectomycorrihizal fungi (sheaths of hyphae grow over and into root, into the extracellular spaces of root cortex), Arbuscular mycorrhizal fungi (branching through root cell plasma membrane). This allows plants to gain nutrition faster through fungi mycelium
What is the reproduction of fungi?
Can be sexual or asexual, spores (haploid cell) via wind or water, mycelium (haploid cells) and asexual reproduction: moulds/yeasts
What are the characteristics of Choanoflagellates?
Unicellular or colonial, mainly freshwater/marine, closest living relative to animal and can be asexual or through sexual reproduction.
