classification and evolution Flashcards
what is classification
arranging organisms into groups based on their similarities and differences
what is taxonomy
the study of classification
what are the three domains and what organisms are contained in each domain
Eukarya- 80s ribosomes
Bacteria- 70s ribosomes
archaea- 8/10 proteins and 70s ribosomes
how are organisms organised
taxonomic hierarchy
what are the five kingdoms and what are their characteristics
prokaryotes- unicellular, no membrane bound organelles
animalia- multicellular, no cell wall, no chloroplasts e.g bacteria
plantae- multicellular, contain chlorophyll, food stored as starch e.g moss
fungi- chitin cell wall, multi/uni cellular, membrane bound organelles e.g mushrooms
protoctist- mainly unicellular, some contain chloroplasts some parasitic e.g alagae
animalia- eukaryotic, multicellular e.g fish
what are the eight levels of taxonomic hierarchy in order
domain
kingdom
phylum
class
order
family
genus
species
what is the nomenclature used for classification called and how does it work
binomial system
first part of the name is the genus name and has a capital letter, the second part is the species name and begins with a lower case
what is phylogeny
the study of evolutionary history of groups of organisms
according to phylogeny what does species mean
the smallest group that shares a common ancestor
what evidence has led to the development of classification systems
molecular evidence- analysing similarities in proteins and DNA
new technology - better microscopes to study DNA
cellular evidence- the bonds in lipids in the cell membrane of Bacteria and Archaea are different
what is variation
differences that exist between individuals
what is intraspecific variation
variation within a species
what is interspecific variation
variation between species
what is continuous variation and give some examples
when the individuals in a population vary within a range, no distinct categories e.g height, mass, milk yield
what is discontinuous variation and what are some examples
when there are two or more distinct categories, no intermediates
e.g blood groups, colour of plants, seed shape
what are some causes of variation
genetic factors- individuals of the same species have the same genes but different versions called alleles, this makes up the genotype and differences in the genotype result in a varied phenotype
environmental factors- climate, food, lifestyle
what does standard deviation tell you
how much the values in a single sample vary
what does each element in the standard deviation calculation represent
S= standard deviation
E= sum of
x= value in data set
x with line on top- mean
n= number of values
what does the null hypothesis state
that there is no correlation between factors investigated
what are adaptations
features that increase chances of survival and reproduction
what are behavioural adaptions and give examples
way an organism acts
possums play dead
what are physiological adaptations and Gove some examples
processes inside an organisms body
bears hibernate (lower their rate of metabolism)
what are anatomical adaptations and give some examples
structural features of an organisms body
otters are streamlined
what is convergent evolution
when two species evolve similar characteristics due to being in similar environments
what were Darwin’s key observations
organisms produce more offspring than survive
variation in characteristics of the same species
some characteristics can be passed onto next generation
individuals best adapted are more likely to survive
what is the theory of natural selection
individuals within a population show variation in their phenotypes
selection pressures such as disease can create struggle for survival
individuals with better adaptations are more likely to survive and have reproductive success
over time the proportion of population possessing advantageous adaptation increases
what is an example o natural selection
peppered moths and dark coloured moths in Victorian era
what evidence is there to support evolution
fossil record evidence
molecular evidence e.g DNA
molecular evidence like proteins like the sequence of amino acids
what are some of the implications of pesticide resistance for humans
crop infestations, broader pesticides used which could kill useful insects
population of insects could evolve which are resistant to all pesticides
costly and time consuming to make and develop
