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Can you predict what offspring will look like?

Can you predict what offspring will look like?. PUNNETT SQUARES. PUNNETT SQUARES-WHAT IS THE PURPOSE?. ORGANIZE GENETIC INFORMATION PREDICT THE RESULTS OF A GENETIC CROSS SHOWS GENOTYPES AND PHENOTYPES OF THE OFFSPRING It was proposed by the English geneticist, Reginald Punnett. Phenotype.

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Can you predict what offspring will look like?

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  1. Can you predict what offspring will look like? PUNNETT SQUARES

  2. PUNNETT SQUARES-WHAT IS THE PURPOSE? • ORGANIZE GENETIC INFORMATION • PREDICT THE RESULTS OF A GENETIC CROSS • SHOWS GENOTYPES AND PHENOTYPES OF THE OFFSPRING • It was proposed by the English geneticist, Reginald Punnett

  3. Phenotype • the observable physical characteristics of an organism • the things you can see • The expressions of genotypes

  4. GENOTYPE • LETTER COMBINATION FOR TRAITS • LETTERS ARE IN PAIRS • EX. TT, T t, t t

  5. Dominant & recessive alleles (Fig. 10.7):

  6. Punnett Squares • 1. Write down the genotypes of both parents • Male parent = Tt • Female parent = Tt • 2. Write down the possible gametes each parent can make. • Male gametes: T or t • Female gametes: T or t

  7. 3. Create an empty Punnett square • 4. Fill in the Punnett square with the possible genotypes of the offspring

  8. Punnett square with genotypes and phenotypes Understanding Physical Anthropology and Archaeology, 8th ed., p. 55

  9. Purebred Dominant x Purebred Recessive(PP x pp) • Genotype Ratio: All Pp • Phenotype Ratio: All Dominant

  10. 2. Purebred Dominant x Hybrid (BB X Bb) • Genotype Ratio: ½ BB: ½ Bb 1BB:1Bb 50%BB:50%Bb • Phenotype Ratio: All Dominant

  11. 3. Hybrid x Hybrid (Bb x Bb) • Genotype Ratio: ¼ BB: ½ Bb: ¼ bb 1BB:2Bb:1bb 25%BB:50%Bb:25%bb • Phenotype Ratio: 3Dominant: 1Recessive

  12. 4.) Hybrid x Purebred recessive Bb x bb Genotype Ratio 2Bb:2bb Phenotype Ratio ½ Dominant: 1/2 Recessive

  13. Summary of the 4 crosses

  14. Dihybrid Cross • A dihybrid cross examines 2 different genes. • RULES: • Do not cross traits • Capital letters must go first for each trait • Each organism is going to have two genotypes and phenotypes

  15. Dihybrid Cross: F1 cross

  16. Vocab Review • Sections of DNA are now called ________. • _______ are different forms of the same gene. • An individual with two identical alleles is termed ____________. • An individual with two different alleles, is termed ____________. • ____________ refers to the letter combination for traits. • ____________ refers to the physical appearance of an organism.

  17. Vocab Review • Sections of DNA are now called genes. • Alleles are different forms of the same gene • An individual with two identical alleles is termed homozygous • An individual with two different alleles, is termed heterozygous • Genotype refers to the letter combination for traits. • Phenotype refers to the physical appearance of an organism.

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