Unit 10 - Classification and Evolution Flashcards
Define classification.
Classification = the process of sorting living organisms into groups
What is classification used for?
- identifying species
- predicting characteristics of species
- finding evolutionary links between species
Define binomial nomenclature.
Binomial nomenclature = Scientific naming of a species using the genus and the species
Define domain.
Domain = highest taxonomic rank in the hierarchical classification system
Define kingdom.
Kingdom = second highest taxonomic rank in the hierarchical classification system
Define species.
Species = organisms which can reproduce to produce fertile offspring, lowest taxonomic rank in the hierarchical classification system
Define prokaryotic.
Prokaryotic = organisms with no membrane-bound organelles
Define eukaryotic.
Eukaryotic = organisms which contain membrane-bound organelles
Define autotrophic.
Autotrophic = an organism which can produce its own food from light, water, carbon dioxide or other chemicals
Define heterotrophic.
Heterotrophic = an organism which eats other organisms for energy and nutrients
Define saprotrophic.
Saprotrophic = an organism which eats non-living organic matter (detritus) at a microscopic level
Who first suggested binomial nomenclature and the hierarchical classification system?
Carl Linnaeus.
Who proposed the protoctista kingdom in addition to animal and plant kingdoms?
Ernst Haeckel.
Who proposed the five kingdom classification system?
Robert Whittaker.
Who proposed the three domain classification system?
Carl Woese.
What are the seven taxonomic groups in the Linnaean classification system?
Kingdom
Phylum
Class
Order
Family
Genus
Species
What are the five kingdoms in the older classification system?
Prokaryotae
Protoctista
Fungi
Plantae
Animalia
What are the features of organisms in the Prokaryotae kingdom?
- Unicellular
- No nucleus or membrane-bound organelles
- Have a single circular chromosome
- Most have a peptidoglycan/murein cell wall which may be associated with a slime layer/capsule
70s ribosomes - No visible feeding mechanism - nutrients are absorbed through the cell wall or produced internally by photosynthesis
- Reproduce by binary fission
What are the features of organisms in the Protoctista kingdom?
- Mainly unicellular
- Have a nucleus and membrane-bound organelles
- Some have chloroplasts
- Some are sessile
- Some move by cilia, flagella or amoeboid mechanisms
- Either autotrophic, heterotrophic or both - some are parasitic
What are the features of organisms in the Fungi kingdom?
- Can be unicellular or multicellular
- Have a nucleus and membrane-bound organelles
- Have a chitin cell wall
- No chloroplasts
- No mechanisms for locomotion
- Most have a body or mycelium made of threads or hyphae
- Saprophytic feeders - some are parasitic
- Most store food as glycogen
What are the features of organisms in the Plantae kingdom?
- Multicellular
- Have a nucleus and membrane-bound organelles, including chloroplasts
- Have a cellulose cell wall
- Most do not move
- Gametes of some plants move using cilia or flagella
- Autotrophic feeders
- Store food as starch
What are the features of organisms in the Animalia kingdom?
- Multicellular
- Have a nucleus and membrane-bound organelles
- No cell wall
- No chloroplasts
- Move using cilia, flagella or contractile proteins, sometimes in the form of muscular organs
- Heterotrophic feeders
- Store food as glycogen
What are the three domains proposed by Woese?
Archaea
Bacteria
Eukarya
What are the features of Archaea?
- 70s ribosomes
- RNA polymerase contains 8-10 proteins
What are the features of Bacteria?
- 70s ribosomes
- RNA polymerase contains 5 proteins
What are the features of Eukarya?
- 80s ribosomes
- RNA polymerase contains 12 proteins
What did Woese divide the Prokaryotae kingdom into?
Archaebacteria and Eubacteria.
What is the difference between Archaebacteria and Eubacteria?
Archaebacteria are known as ancient bacteria, while Eubacteria are known as true bacteria. Eubacteria are found in all environments, whereas Archaebacteria are more likely to be found in environments with extreme conditions.
