Classification Flashcards
What is classification and why do we do it?
Classification is the process of placing organisms into taxonomic groups based on similarities
Convenience , identify organisms & their relationships
What are the 8 taxonomic groups
Domain , Kingdom , Phylum, Class , Order , Family , Genus , Species
What are the 5 kingdoms ?
Prokaryote
Protoctista
Fungi
Plantae
Animalia
What is the Binomial naming system and why do we use it?
the genus and species are used . only the Genus is capitalised
e.g Homo sapiens. Sometimes they’re in italics.;
Its a universal language so we use it
What is phylogeny?
Grouping together organisms that share a common ancestor
What’s the difference between natural and artificial classification?
ARTIFICIAL - based on limited characteristics while not looking at evolutionary past . Not a lot of info
NATURAL - based on many characteristics by showing the evolutionary relationships there’s a lot of info to be provided
What is the 3 domain classification system ?
based on ribosomal RNA.
Bacteria , Archaea and Eukaryot
What are the differences between the Domain and kingdom classification?
Domain :
3 domains , 6 kingdoms , based on RNA , all eukaryotes are in the same domain
Kingdom:
1 domain , 5 kingdoms where all the eukaryotes are divided , based on physical and genetic similarities.
What is the evidence for classification systems
Biological molecules - DNA is used to make molecules for replication and respiration which is essential for all living things so they’ll all have a variant of these so it can show how closely related they are.
Cytochrome C - protein used in respiration. The sequence of amino acids that make the protein help to draw conclusions on how closely related species are
State the features Prokaryotae
Unicellular
Small ribosomes
No Nucleus
Looped of naked DNA
No membrane bound organelles
State the features of Protoctista
Unicellular
nucleus & membrane bound organelles
autorophic & heterotrophic nutrition
e.e algae
What does autotrophic and heterotrophic mean ?
autorophic - absorb small to large molecules
heterotrophic - digest large to small molecules
state the features of Fungi
multicellular - sometimes unicellular
saprophytic - cause the decay of matter
have mycelium which consists of a network of hyphae
walls are made from chitin
state the features of Plantae
multicellular
have a cellulose cell wall
autotrophic
have chlorophyll for photsynthesis
State the features of Animialia
Multicellular
can move around
heterotrophic
What are the 3 domains
Bacteria
Archaea
Eukaryote
Compare the features of Bacteria to Eukaryote and Archaeae
Different cell membrane structure (lipids vs peptidoglycan)
Different enzymes to make DNA - RNA polymerase vs DNA polymerase
Flagella with different internal structures
No proteins bound to their genetic material
What features of Archaea and Eukaryotes are similar
Similar enzymes for building RNA - RNA polymerase
Similar mechanisms for DNA replication and building RNA
Production of some proteins that bind to their DNA
why do we use the 3 domains classification instead of kingdom
phylogeny fits better
there are fundamental differences between the domains
bacteria and arcahaea have different DNA replication
What is natural selection?
How the features of the environment apply a selective force on the reproduction of individuals in a population.
How did Darwin contribute to the theory of evolution?
more offspring then parents
variation in species
offspring’s looked similar to their parents
better adapted induvials survived and reproduced
How did Wallace contribute to the theory of evolution
similar ideas to Darwin
arrived to the conclusion independently
more evidence was present
What evidence is there to support the theory of evolution?
Fossils - Darwin saw that organisms changes over time. They’re also used to help link organisms together over time. Fossils can be dated.
Cytochrome C- protein used in all living organisms so amino acid sequence must be the same
What is continuous variation ?
Variation that can take value between 2 intermediates - a range of values
What is discontinuous variation
When there are 2 or more distinct groups with no intermeiates
What is interspecific variation
Variation between species
What are the genetic causes of variation
Inherited combination of alleles
Mutations
Meiosis
What are the environmental causes of variation?
Sunlight
Food and water availability
What factors of variation can be both environmental and genetic
skin colour - inherited and the sun
height - both inherited and due to the type of food we eat
Describe types of evidence that support the theory of evolution
similarities in DNA
similarities in amino acid sequence
similarities in. cytochrome c
evolution within humans.
Similarities imply a close relationship
What is an adaptation ?
A characteristic which increases the chances of survival
what are the 3 types of adaptaions
behavioural
anatomical
physiological
what is a behavioural adaptation
way in which behaviour is adapted for survival
what is anatomical adaptation ?
Adaptations in an organisms structure
what is physiological adaptations
They affect away in which a process works
Give examples of anatomical adaptations is marram grass
long roots
curled leaves
hair on lower epidermis
few stomata
thick waxy cuticle
