classification Flashcards
what is classification
reflecting evolutionary relatedness
use a phylogenetic method
evolutionary history can be shown using a phylogenetic tree
what is taxonomy
the identification and naming of organisms
what is a hierarchy
a system of ranking in which the small groups are components of larger groups
what is a taxon
any group within a system of classification
what does discrete mean
they can only be classified into one group
what are the three domains
archaea
eubacteria
eukaryota
what is archae
bacteria - generally which has an unusual metabolism or characteristic
what is eubacteria
eg salmonella - prokaryotes
what is eukaryota
plantae animalia fungi and protoctista
what are the five kingdoms
plantae animalia fungi prokaryote protoctista
characteristics of eukaryote
uni or multicellular organelle and nuclear membranes
characteristics of prokaryote
unicellular,, no membrane bound organelles, no nuclear membrane, non cellulose cell wall
what is the phylogenetic hierarchy
kingdom phylum class order family genus species
how are organelles placed in the phylogenetic hierarchy
placed into groups (taxons) based on their increasing similarity
characteristics of prokaryotic
single celled no nucleus mesosome in some 70s ribosomes no ER no vacuole cell wall made of peptidogcylan saprophytic, parasitic or autotrophic feeders no nervous coordination
characteristics of protoctista
eukaryotic single or multi cellular nucleus mitochondria some have chloroplasts 80s ribosomes ER some have a vacuole cell wall - cellulose - none nutrition - heterotrophic or autotrophic no nervous coordination
characteristics of plantae
eukaryotic multicellular nucleus mitochondria chloroplasts 80s ribosomes ER large central vacuole cellulose cell wall autotrophic feeders no nervous coordination
characteristics of fungi
eukaryotic single celled nucleus mitochondria chloroplasts 80s ribosomes vacuole
what is the binomial system and what is it made up of
organisms are given 2 latin names
first is the genus and second is the species
what are the advantages of the binomial naming system
unambiguous and allows us to see what is closely related
what is a species
a group of similar organisms that have certain features in common
the similar anatomically and biochemically
capable of interbreeding to produce fertile offspring
what is the morphological defintion
if 2 organisms look very similar they are likely to be members of the same species. sexual dimorphism needs to be taken into account
juveniles will look different
what is biodiversity
number and variety of organisms found within a specified geographic region
the variety of different types of life found on earth and variations within a species
refers to the variety of life on earth at all its levels, genes to ecosystems
what is a homologous structure
a similar arrangement of component parts and a similar developmental origin but different functions
what is an analogous structure
have a corresponding function and similar shape but different developmental origin
what is a pentadactyl limb
a limb with 5 digits
what is divergent evolution
a common ancestral structure has evolved and performs different functions e.g. pentadactyl
what is convergent evolution
structure evolve similar properties but have different developmental origins such structures are analogous e.g. butterfly, sparrow, bat
describe the process of natural selection
1) all living organisms show genetic variation due to gene mutations
2) those with favourable genes are more likely to survive
3) surviving organisms reproduce and pass on the favourable gene to their offspring
4) over tie the favourable allele becomes more highly represented in the population
give examples of physiological traits
- mammals and birds are endothermic and must avoid wasting energy trying to maintain body temp in the cold
- during hibernation a polar bear resets its body thermostat to use less energy so body temp drops to 2c
- leaves fall off deciduous plants when the temp and light decrease in autumn. this way they do not lose water by transpiration
give examples of behavioural traits
- many plants flower in spring when pollination insects have emerged. if it flowered earlier it would not be pollinated
- mating rituals in animals include the displaying of a peacocks tail or dances performed by flamingo to increase the chance of reproducing
give examples of anatomical traits
- sharks, dolphins and penguins have streamlined bodies without this body shape they would be less efficient at catching food or escaping predators
- flowers with honey or nectar guides sometimes called beelines. they indicate the centre of the flower the source of the nectar. a flower without these lines would attract fewer pollinators
