Classification And Evolution Flashcards
What are the 7 taxonomic groups in order?
Kingdom Phylum Class Order Family Genus Species
Who created the hierarchical classification system?
Carl Linnaeus
Why do scientists classify organisms?
To identify species
To predict characteristics
To find evolutionary links
What are the 3 domains?
Archaea
Bacteria
Eukarya
What is a species?
A group of organisms that can produce fertile offspring
What is binomial nomenclature?
All species are given a scientific name consisting of 2 parts. The genus and the species
What’s are the 5 kingdoms?
Prokaryotae Protoctista Fungi Plantae Animalia
Features of prokaryotae?
Unicellular
No nucleus or membrane bound organelles
No visible feeding mechanisms
General features of protoctista?
Mainly unicellular
A nucleus and membrane bound organelles
Some have chloroplasts
Nutrients acquired by photosynthesis
Some are sessile, others move by cilia or flagella.
Fungi general features?
Uni or multicellular
Have a nucleus and membrane bound organelles and a cell wall made of chitin
No chloroplasts or chlorophyll
No locomotion mechanism
Have a body or mycelium made from threads or hyphae
Nutrients acquired by absorption (saphrophytic)
Store food as glycogen
General features of plantae?
Multicellular
Have a nucleus, membrane bound organelles and cell wall made of cellulose
All contain chlorophyll
Most do not move
Nutrients acquired by photosynthesis
Store food as starch
Features of animalia?
Multicellular
Nucleus and membrane bound organelles
No chloroplasts
Move with aid of cilia, flagella or contractile proteins
Nutrients acquired by ingestion
Food stored as glycogen
How did Carl Woese’s system classify organisms?
Groups organisms using differences in sequences of nucleotides in the cells rRNA
What are archaebacteria?
Can live in extreme environments, these include thermal air vents, anaerobic conditions and highly acidic environments. Eg methanogens
What is phylogeny?
The name given to evolutionary relationships between organisms
What does phylogeny show?
It reveals which group a particular organisms is related to and how closely related the organisms are.
If branches are closer together on phylogenetic trees, what does this mean?
There is a closer evolutionary relationship
Where is the earliest species found on a phylogenetic tree?
At the base of the tree
What are 2 descendants from the same node called?
Sister groups
Advantages of Phylogenetic classification?
Can be done without reference to Linnaean classification.
Phylogeny produces a continuous tree whereas classification requires discrete taxonomic grouping.
The hierarchy nature of Linnaean classification can be misleading as it implies that different species within the same rank are equivalent.
What is the evidence for Evolution?
Palaeontology
Comparative anatomy
Comparative biochemistry
What is the fossil record?
Where different layers of rock correspond to different geological eras ( most recent on top). The fossils in each layer change over time abs this can prove how organisms have changed over time too
What evidence is provided by the fossil record?
Complex fossils found in more recent strata whereas simpler organisms fossils found further down = supports the evolutionary theory.
The sequence in which the organisms are found matches their ecological links to each other. Plant fossils appear before animal fossils, supporting the fact that animals require plants to survive.
Can show similarities in the anatomy of fossil organisms, can show evolution from a common ancestor
Fossils allow relationships between extinct abs living organisms to be investigated