Studied by 4 people
gene pool
sum total of all the alleles of all the genes present in a population
allele frequency
relative frequency of a particular allele (in comparison to the other alleles of the same gene) in a population
genetic drift
change in alleles frequency in a gene pool of a population due to chance events. can occurs in two situation: the bottleneck effect and founder effect
bottleneck effect
when natural disasters lead to a sudden decrease in the population that may not represent the genetic diversity of the original population
founder effect
when a small subset of a population breaks away from the larger population to colonize a new area and the population that branches off may not be an exact genetic representation of the original population
neo-darwinism
the combined work of many scientists to explain natural selection on the foundation of mendelian genetics
stabilizing selection
natural selection that favours the average individual with intermediate forms of the trait and eliminates extreme forms
directional selection
favours one extreme form id the trait over all other forms
disruptive selection
natural selection where both extremes forms of the traits are favoured over the intermediate form
artificial selection
when people select traits to be represented in the next generation
linked genes
genes that are found on the same chromosome and are close togethef
unlinked genes
genes that are found on different chromosomes
dihybrid cross
the inheritance of two traits
gene loci
specific location of a gene in a chromosome
discrete variation
traits where individuals are clearly one phenotype or another
continuous variation
a spread called a normal distribution that is plotted as a bell-curve
polygenic inheritance
when a trait is controlled by many genes interacting together
speciation
the process by which new species arise
reproductive isolation
a driver of speciation when barriers prevent populations of the same species from interbreeding
allopatric speciation
speciation from geographical factors
sympatric speciation
speciation that happens in the same location due to isolating mechanisms
temporal isolation
a type of reproductive isolation that results from differences in timing of the reproductive cycle
behavioural isolation
a type of reproductive isolation that results from environmental factors
adaptive radiation
evolution of multiple new species from an ancestral species to occupy different ecological niches
hybridisation
interbreeding between two different species that leads to a new species
polyploidy
when a diploid cell or organism acquired one or more additional sets of chromosomes
allopolyploidy
a special case of polyploidy where a hybrid has multiple chromosomes sets that are derived from the different parental species
