Unformatted text preview: ¢ What is the probability that event 1 AND event 2 will occur? What AND P(1 and 2) = probability of event 1 x probability of event 2 P(1 and Sum rule: probability of either of two mutually probability exclusive events occurring is the sum of their individual probabilities individual
â€¢ What is the probability that event 1 OR event 2 will occur? What OR P(1 or 2) =probability of event 1 + probability of event 2 P(1 or Probability and Mendelâ€™s Results Probability and Mendelâ€™s Results 0 Cross Yy x Yy pea plants Chance of Y sperm uniting with a Y egg Â½ chance of sperm with Y allele Â½ chance of egg with Y allele Chance of Y and Y uniting = Â½ x Â½ =1/4 Chance of Yy offspring Â½ chance of sperm with y allele and egg with Y allele Â½ chance of sperm with Y allele and egg with y allele Chance of Yy â€“ (Â½ x Â½) + (Â½ x Â½) = 2/4 , or 1/2 Further crosses confirm predicted Further crosses confirm predicted ratios 0 Genotypes and Phenotypes Genotypes and Phenotypes 0 Phenotype â€“ observable characteristic of an organism Genotype â€“ pair of alleles present in an individual Homozygous â€“ two alleles of trait are the same (yy) (YY) Heterozygous â€“ two alleles of trait are different (Yy) Genotypes versus phenotpyes Genotypes versus phenotpyes 0 Test cross reveals unkown genotpye Test cross reveals unkown genotpye
? geno tester ? geno tester 0 A dihybrid is an individual that is heterozygous at two genes Mendel designed experiments to determine if two genes segregate independently of one another in dihybrids First constructed true breeding lines for both traits Crossed them to produce dihybrid offspring Examined the F2 for parental or recombinant types (new combinations not present on the Dihybrid crosses reveal the law of Dihybrid crosses reveal the law of independent assortment Results of Mendels dihybrid crosses Results of Mendels dihybrid crosses F2 generation contained both parental types and recombinant types Alleles of genes assort independently, and can thus appear in any combination in the o...
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 Spring '03
 Larkin
 Genetics, ryts ryts ryts

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