Process of Evolution: GENE FLOW Flashcards
Forces that disrupt HW equilibrium
Genetic drift (chance in small populations)
Mutation
Migration and gene flow
Non-random mating
Natural selection
What are the 5 conditions that must be met for HW equilibrium to be maintained?
Large population size
No mutation
No migration (gene flow)
Random mating
No natural selection
What is the Hardy-Weinberg (HW) equilibrium formula?
P^2+2pq+q ^2=1
What is genetic drift?
A change in allele frequencies due to random events in small populations.
What is the bottleneck effect?
A sharp reduction in population size due to environmental events, leading to altered allele frequencies.
How do you calculate allele frequency from genotypes?
From 64 RR, 32 Rr, 4 rr →
R = (128 from RR) + (32 from Rr) = 160
r = (32 from Rr) + (8 from rr) = 40
Total alleles = 200 → p = 0.8, q = 0.2
What is the founder effect?
Allele frequencies change due to migration of a small founding group.
What is gene flow?
Movement of alleles between populations.
WHAT IS THIS FROM THE HW E. FORMULA: 𝑝^2
frequency of homozygous dominant (RR
WHAT IS THIS FROM THE HW E. FORMULA: 2pq
frequency of heterozygous (Rr)
WHAT IS THIS FROM THE HW E. FORMULA: q^
2
frequency of homozygous recessive (rr)
How does mutation affect HW equilibrium?
It introduces new alleles
How does gene flow disrupt HW equilibrium?
Alleles move between populations, changing allele frequencies.
What is non-random mating?
Mating based on preference or relatedness, affecting genotype distribution without changing allele frequency.
How does natural selection disrupt HW equilibrium?
It favors individuals with beneficial traits, altering genotype frequencies.
