Gene pool; is the sum of all the alleles in a population. The members
of each population, therefore have the same gene pool.
Allele frequency; refers to the population or percentage of a particular
allele of a gene in a population, relative to other alleles of the same
gene.
The Hardy-Weinberg equation; is an equation to calculate allele and
genotype frequencies within a population
p = represents the frequency of the dominant allele,
q = represents the frequency of the recessive allele,
p + q =1.0
However in diploid organisms alleles occur in pairs. In order
to calculate genotype frequency rather than allele frequency,
a second equation is used; p2 + 2pq + q2 = 1.0
where; p2 = frequency of the AA genotype, 2pq = frequency
of the Aa genotype, q2 = frequency of aa genotype
The Hardy-Weinberg priciple; the frequency of dominant and
recessive alleles in a popuation will remain constant from generation
to generation provided certain conditions are met, these are;
1. The population is large
2. Mating is random
3. No mutations occur
4. There is no immigration into or emmigration out of the population
5. All genotypes are equally fertile so that no natural selection is taking place
The name given to a change in allele frequency due to change is called genetic drift