CBSE · Class 12 · Biology · EvolutionState the Hardy-Weinberg Principle. List five factors known to disturb Hardy-Weinberg genetic equilibrium.

Hardy-Weinberg Principle

\nThe Hardy-Weinberg principle states that allele frequencies and genotype frequencies in a large, randomly mating population remain constant and stable from generation to generation, provided there are no evolutionary forces acting upon it. \nThis genetic equilibrium is mathematically expressed as: $$p^2 + 2pq + q^2 = 1$$ (where $p$ and $q$ represent the frequencies of individual alleles, $p^2$ is homozygous dominant, $2pq$ is heterozygous, and $q^2$ is homozygous recessive). Any deviation in allele frequency indicates evolutionary change.

Five Factors Disturbing Hardy-Weinberg Equilibrium:

1. Gene Flow or Gene Migration: Movement of alleles into or out of a population due to migration.
2. Genetic Drift: Random changes in allele frequencies occurring by chance in small populations.
3. Mutation: Sudden permanent alterations in DNA that introduce new alleles into the gene pool.
4. Genetic Recombination: Recombination of alleles during crossing over in meiosis.
5. Natural Selection: Differential reproduction where advantageous traits are selected by nature.