Hardy-Weinberg Equilibrium

Slides:



Advertisements
Similar presentations
Day 5: Causes of Microevolution
Advertisements

How do we know if a population is evolving?
Hardy-Weinberg Principle
KEY CONCEPT Hardy-Weinberg equilibrium provides a framework for understanding how populations evolve.
Hardy-Weinberg Equilibrium
 Establishes a benchmark from a non- evolving population in which to measure an evolving population.  Investigates the properties of populations that.
The Hardy-Weinberg Equilibrium Allele Frequencies in a Population G.H. Hardy English Mathematician Dr. Wilhelm Weinberg German Physician.
Population Genetics.
PoPuLaTiOn GeNeTiCs. PoPuLaTiOn GeNeTiCs ( Heredity was not understood during Darwin’s time) Definition - science of genetic changes in populations. Populations.
PROCESS OF EVOLUTION I (Genetic Context). Since the Time of Darwin  Darwin did not explain how variation originates or passed on  The genetic principles.
Introducing the Hardy-Weinberg principle The Hardy-Weinberg principle is a mathematical model used to calculate the allele frequencies of traits with dominant.
Evidence for Evolution- Hardy-Weinberg equation
The Hardy-Weinberg Equilibrium
Population Genetics and Evolution. Darwin’s Observations (review) Galapagos Islands Many similar species had slight differences Favorable variations allow.
Hardy-Weinberg Equilibrium Honors Biology. Is evolution occurring right now?  How might a scientist tell if evolution is occurring within a population?
Review of Natural Selection Types. Effects of Selection See Fig Coat color.
Introduction to Hardy- Weinberg Principle  How do we know the population is evolving?  We can tell if the population is evolving if we measure genetic.
Genetic Drift Random change in allele frequency –Just by chance or chance events (migrations, natural disasters, etc) Most effect on smaller populations.
The Hardy-Weinberg Principles Changing Populations.
Maintaining Genetic Variation (Population Equilibrium) Populations have TWO competing factors: Remaining stable (not evolving) vs Changing (evolving)
Population Genetics and Evolution AP Biology. Population Genetics Macroevolution: evolution on a grade scale Ex. Evolution of a new species - modern camel.
Genetic Equilibrium. A population is a group of individuals of a species that lives in the same area at the same time.
How to: Hardy - Weinberg
How do we know if a population is evolving?
Terms: Population: Group of interbreeding or potentially interbreeding organisms Population Genetics: Branch of genetics that studies the genetic makeup.
CHAPTER 23.1 Population Genetics. Quick Review: Natural Selection Variation  Natural Selection  Speciation Organisms better suited to the environment.
Mechanisms of Evolution Hardy-Weinberg Law.  The Hardy–Weinberg principle states that the genotype frequencies in a population remain constant or are.
Changing Allele Frequency Chapter 23. What you need to know! The conditions for Hardy-Weinberg Equilibrium How to use the Hardy-Weinberg equation to calculate.
MICROEVOLUTION. POPULATION GENETICS PHET NATURAL SELECTION Mutation  Variation  Natural Selection  Speciation.
 A llele frequencies will remain constant unless one or more factors cause the frequencies to change.  If there is no change, there is no evolving.
1. Define the following terms:  Genetic drift: random change in a gene frequency that is caused by a series of chance occurrences that cause an allele.
Population Genetics. Relative Frequency of an Allele The number of times an allele occurs in the gene pool, given as a percentage Relative frequency has.
Evolutionary Change in Populations
Hardy-Weinberg Equilibrium Population Genetics and Evolution.
KEY CONCEPT Hardy-Weinberg equilibrium provides a framework for understanding how populations evolve.
Godfrey Hardy ( ) Wilhelm Weinberg ( ) Hardy-Weinberg Principle p + q = 1 Allele frequencies, assuming 2 alleles, one dominant over the.
KEY CONCEPT Hardy-Weinberg equilibrium provides a framework for understanding how populations evolve.
Gene Pool: All the genes of all the members in a population. Allele Frequency: Percent of each allele in the population. Genetic Equilibrium: Allele frequencies.
12. 4 Population Genetics.  Definition = study of genetics of groups of interbreeding individuals  Gene pool = all of the genes in a population at any.
Meet My Good Friends Hardy and Weinberg!! Biologists use models to study populations. Biologists use models to study populations. Hardy and Weinberg.
Hardy-Weinberg Equilibrium Honors Biology. Is evolution occurring right now?  How might a scientist tell if evolution is occurring within a population?
Hardy-Weinberg Equilibrium
Hardy-Weinberg Theorem
HARDY WEINBERG.
KEY CONCEPT Hardy-Weinberg equilibrium provides a framework for understanding how populations evolve.
What we know….
KEY CONCEPT Hardy-Weinberg equilibrium provides a framework for understanding how populations evolve.
KEY CONCEPT Hardy-Weinberg equilibrium provides a framework for understanding how populations evolve.
Hardy-Weinberg Equilibrium and Equations
Population Genetics & Hardy - Weinberg
Hardy Weinberg What the heck is that?.
1. Sexual Selection In order for random mating to occur, all members of the population must have equal.
Lecture: Natural Selection and Genetic Drift and Genetic Equilibrium
Measuring Evolution of Populations
Hardy-Weinberg Equilibrium and Equations
KEY CONCEPT Hardy-Weinberg equilibrium provides a framework for understanding how populations evolve.
Hardy – Weinberg Theorem
Allele frequencies when populations are NOT evolving
Measuring Evolution of Populations
Hardy-Weinberg Equilibrium Model
KEY CONCEPT Hardy-Weinberg equilibrium provides a framework for understanding how populations evolve.
KEY CONCEPT Hardy-Weinberg equilibrium provides a framework for understanding how populations evolve.
KEY CONCEPT Hardy-Weinberg equilibrium provides a framework for understanding how populations evolve.
Hardy – Weinberg Theorem
KEY CONCEPT Hardy-Weinberg equilibrium provides a framework for understanding how populations evolve.
Hardy Weinberg.
Hardy – Weinberg Equilibrium
KEY CONCEPT Hardy-Weinberg equilibrium provides a framework for understanding how populations evolve.
4-Population Genetics Notes
HARDY-WEINBERG & EVOLUTION
Presentation transcript:

Hardy-Weinberg Equilibrium Honors Biology

Is evolution occurring right now? How might a scientist tell if evolution is occurring within a population?

Hardy-Weinberg Equilibrium Biologists use models to study populations Hardy-Weinberg equilibrium is a type of model Provides a framework for understanding how populations evolve

Hardy-Weinberg Equilibrium Conditions Genotype frequencies stay the same (no microevolution) if all 5 conditions are met: Very large population size Isolation from other populations No Mutations Random Mating No natural selection

The Hardy-Weinberg Equation Uses frequencies of alleles in a population’s gene pool to determine if (micro)evolution is occurring If allele frequencies change over time, the population is evolving If allele frequencies are stable, the population is at equilibrium

Hardy-Weinberg Equation p + q = 1 p = frequency of dominant allele q = frequency of recessive allele p2 + 2pq + q2 = 1 p2 = frequency of homozygous dominant genotype (AA) 2pq = frequency of heterozygous genotype (Aa) q2 = frequency of homozygous recessive genotype (aa)

Solve this story problem In pigs, the allele for black coat is recessive to pink coats. B = pink; b = black Calculate q2 for the illustration shown below. q2 = 0.25 (4/16)

Find q. Find p. Find 2pq. q = 0.5 p = 0.5 2pq = 0.5 This means 50% of the pink pigs are heterozygous.

Solve this story problem In a certain flock of sheep, 4 percent of the population has black wool and 96 percent has white wool. If black wool is a recessive trait: What percentage of the population is homozygous black? (q2) What percentage of the population is heterozygous for this trait? (2pq) What percentage of the population is homozygous white? (p2)