Teacher Notes
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Teacher Notes![]() Gene Pool and Natural SelectionSuper Value Laboratory KitMaterials Included In KitGene Pool and Natural Selection Worksheet Additional Materials Required(for each lab group) Safety PrecautionsDo not use pop beads with small children as they can inhale or ingest them. Follow all other normal laboratory safety rules. DisposalAll materials may be stored for future use. Teacher Tips
Correlation to Next Generation Science Standards (NGSS)†Science & Engineering PracticesAnalyzing and interpreting dataDeveloping and using models Disciplinary Core IdeasMS-LS1.B: Growth and Development of OrganismsMS-LS3.A: Inheritance of Traits HS-LS3.B: Variation of Traits Crosscutting ConceptsScale, proportion, and quantityCause and effect Performance ExpectationsMS-LS3-2. Develop and use a model to describe why asexual reproduction results in offspring with identical genetic information and sexual reproduction results in offspring with genetic variation. Answers to Questions{10335_Answers_Table_1}
p = 0.6
p = 0.51
The gene pools are not identical, but they are very similar. {10335_Answers_Table_2}
p = 0.65
The frequency of W in the gene pool has decreased from 0.40 to 0.35 in this example and the frequency of red has gone up from 0.60 to 0.65.
The W gene is not likely to be completely eliminated from the gene pool because of the heterozygous individuals carrying the recessive gene. Recommended Products
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Student Pages
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Student Pages![]() Gene Pool and Natural SelectionIntroductionWhat is a gene pool? What factors affect or change a gene pool over time? Concepts
BackgroundEarly in the 20th century the mathematician G. H. Hardy and the physician W. Weinberg recognized a mathematical relationship that represents the allele frequencies found in a population at equilibrium. The mathematical relationship became known as the Hardy-Weinberg Principle.
No real world population actually meets all of the Hardy-Weinberg criteria. The short term stability of many large populations, however, allows the population to be analyzed with the Hardy-Weinberg Principle and changes in gene frequencies within the gene pool can often be detected and theorized. {10335_Background_Figure_1}
The Hardy-Weinberg Principle’s mathematical statement is shown in Equation 1. {10335_Background_Equation_1}
where p = frequency of allele p The key to utilizing the mathematical statement on real populations depends on knowing the frequency of the homozygous recessive individuals in the population. This is because the phenotype is often clearly recognized and its frequency can be counted. Once q2 is known, then q can be determined by taking the square root of q2. Since p + q = 100% or 1, p can then be calculated once q has been determined. Once p and q are known p2, 2pq and q2 are all easily derived. q2 = 0.36 In summary, for this population the frequencies of alleles and genotypes would be as follows: q = W = 0.6 MaterialsPop beads, red, 60 Safety PrecautionsDo not use pop beads with small children as they might be swallowed or inhaled. Follow other standard laboratory rules. Procedure
Student Worksheet PDF |