Evolution Flashcards
the definition of evolution?
the changes in organisms over generations as a result of genomic variations.
what is natural selection?
it is the non-random increase in frequency of DNA sequence that increase survival and the non-random reduction in the frequency of deleterious sequences.
what are the 3 ways that natural selection can affect the frequency of phenotype?
stablishing selection
directional selection
disruptive selection
what is horizontal gene transfer?
it is where genes are transferred between individuals in the same generation
what is vertical gene transfer?
it is where genes are transferred from parent to offspring as a result of sexual or asexual reproduction.
what is a species?
it is a group of organisms capable of interbreeding and producing fertile offspring, and which does not normally breed with other groups.
what is speciation?
it is the generation of new biological species by evolution as a result of isolation, mutation and selection
state one importance of an isolation barrier
they prevent gene flow between sub populations during speciation.
what types of speciation is a geographical, behavioural and ecological barrier.
geographical barrier leads to allopatric speciation.
behavioural and ecological barriers lead to sympatric speciation.
LOOK AT STABILISING, DIRECTIONAL AND DISRUPTIVE SELECTION GRAPHS!!!!!
