1 / 7

The Hardy-Weinberg Principle

The Hardy-Weinberg Principle. Assessment Statements:. Explain how the Hardy-Weinberg equation is derived Calculate allele, genotype and phenotype frequencies for two alleles of a gene, using the Hardy-Weinberg equation State the assumptions made when the Hardy-Weinberg equation is used.

makara
Télécharger la présentation

The Hardy-Weinberg Principle

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Hardy-Weinberg Principle

  2. Assessment Statements: • Explain how the Hardy-Weinberg equation is derived • Calculate allele, genotype and phenotype frequencies for two alleles of a gene, using the Hardy-Weinberg equation • State the assumptions made when the Hardy-Weinberg equation is used

  3. Hardy-Weinberg is used because it is helpful in determining how fast a population is changing or to predict the outcomes of matings/crosses The parts of the HW equation: p = frequency of the dominant allele (T) q = frequency of the recessive allele (t) Because there is a 100% probability that a gamete will contain either a T or t, then we can state that p + q = 1 (this is b/c whichever chromosomes do not have the dominant allele must carry the recessive allele)

  4. What complicates things is that we usually want to consider diploid organisms (like humans) that carry 2 copies of each gene • Because of this we need to expand our equation to: p2 + 2pq + q2 = 1 • The above equation is known as the Hardy-Weinberg equilibrium and it is reached only if a population is not evolving TT = p2 Tt = 2pq tt = q2

  5. To Help Summarize: p2 + 2pq + q2 = 1 • p = dominant allele frequency • q = recessive allele frequency • p2 = frequency of homozygous dominant • 2pq = frequency of heterozygous • q2 = frequency of homozygous recessive Khan Academy Tutorial

  6. Conditions for Hardy-Weinberg Equilibrium: • No mutations. • Random mating. • No natural selection. (All organisms have the same survival/reproduction rates) • Extremely large population size. (The smaller the population the more likely it is that allele frequencies will fluctuate by chance from one generation to the next; this is called genetic drift) • No gene flow. (No new organisms can move into the population and no organisms can move out of the population)

More Related