genetic information (selection and classification) Flashcards
what is an example of directional selection?
antibiotic resistance
what is directional selection?
individuals with alleles for extreme characteristics are more likely to survive and reproduce
could be in response to an environmental change
what is an example of stabilising selection?
human birth weight
what is stabilising selection?
where individuals with alleles for characteristics towards the middle of the range are more likely to survive and reproduce
environment isn’t changing
reduces the range of possible characteristics
what is phylogeny?
study of the evolutionary history of groups of organisms, showed how closely related organisms are
what does a phylogenic tree show?
how all organisms have evolved from shared common ancestors
first branch point= common ancestor of all family members
closely related species diverged from eachother more recently
what is taxonomy?
science of classification- naming organisms and organising them into groups
what are groups called in taxonomy?
taxa/taxon
what are the three domains?
eukarya, bacteria, archea
what is the order for taxonomy?
domain kingdom phylum class order family genus species
what is a species?
group of similar organisms able to reproduce to give fertile offspring
how is the binomial naming system written>
first part= genus with capital
second part= species with a lower case letter
written in italics
what is courtship behaviour?
behaviours carried out by organisms to attract a mate of the right species
why is courtship behaviour species specific?
allows members of the same species to recognise eachother
prevents interbreeding
more successful reproduction, as mating with the wrong species doesn’t produce fertile offspring
