Download Section 11.4- Hardy-Weinberg Equation

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March 13, 2017
Hardy­Weinberg Principle­ Allele frequencies in a population will remain constant unless one or more factors causes the frequencies to change.
The genotype frequency remains the same when a population is in Hardy­Weinberg equilibrium.
a. Very large population
b. No emigration or immigration
c. No mutations
d. Random mating
e. No natural selection
evolution.
Hardy­Weinberg equilibrium is when a populations allele frequencies remains the same.
A population can never be in Hardy­Weinberg equilibrium because the assumptions cannot be met.
It is still of value because it allows us to detect changes in populations from one generation to the next.
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section11.4 new.notebook
March 13, 2017
Equation:
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p + 2pq + q =1 and p+q=1
p= frequency of dominant allele
q= frequency of recessive allele
p2= individuals that are homozygous dominant.
q2= individuals that are homozygous recessive.
2pq= heterozygous individuals.
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March 13, 2017
Hardy­Weinberg equation can be used in simple dominant­
recessive systems.
The actual genotype frequencies must be known.
If the frequencies do not match the predicted frequencies the population is evolving.
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section11.4 new.notebook
March 13, 2017
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