Chapter 13 – Mendel and the GeneIntroductionMendel’s Experimental SystemGarden Peas: The First Model Organism in GeneticsHow Did Mendel Arrange Matings?PowerPoint PresentationWhat Traits Did Mendel Study?Inheritance of a Single TraitThe Monohybrid CrossSlide 10Dominant and Recessive TraitsSlide 12Slide 13Slide 14A Reciprocal CrossParticulate InheritanceGenes, Alleles, and GenotypesThe Principle of SegregationGenetic Notational ConventionCrossing Pure LinesSlide 21Slide 22Testing the ModelMendel’s Experiments with Two TraitsThe Principle of Independent AssortmentSlide 26Using a Testcross to Confirm PredictionsSlide 28The Chromosome Theory of InheritanceSlide 30Slide 31Slide 32Testing the Chromosome TheoryThe Discovery of Sex ChromosomesSlide 35Incomplete Dominance and CodominanceSlide 37Slide 38Multiple Alleles and Polymorphic TraitsPleiotropySlide 41Slide 42The Physical Environment Also Affects PhenotypeApplying Mendel’s Rules to HumansIdentifying Human Alleles as Recessive or DominantPatterns of Inheritance: Autosomal Recessive TraitsSlide 47Patterns of Inheritance: Autosomal Dominant TraitsSlide 49Is the Trait Autosomal or Sex-Linked?Slide 51Slide 52Slide 53Slide 54Slide 55Chapter 14 – DNA and the GeneWhat Are Genes Made Of?DNA’s Primary StructureDNA’s Secondary StructureHow Do the Old and New DNA Strands Interact?Repairing Mistakes and DamageHow Does DNA Polymerase Proofread?Slide 63Repairing Damaged DNAChapter 15 – How Genes WorkIntroductionThe Central Dogma of Molecular BiologyRNA—the Intermediary between Genes and ProteinsSlide 69The Central DogmaThe Roles of Transcription and TranslationVisualizing the Central DogmaSlide 73The Genetic CodeHow Long Is a Word in the Genetic Code?Slide 76How Did Researchers Crack the Code?Slide 78Slide 79Slide 80******Important Properties of the Code******What Is the Molecular Basis of Mutation?Point MutationsSlide 84Mutations Have Varying Effects on OrganismsSlide 86Slide 87Chromosome-Level MutationsSlide 89Chapter 19 – Analyzing and Engineering GenesSlide 91Using Reverse Transcriptase to Produce cDNAsUsing Plasmids in CloningCutting and Pasting DNASlide 95The Importance of the Creation of Sticky EndsTransformationProducing a cDNA LibrarySlide 99Screening a DNA LibrarySlide 101Slide 102Slide 103The Polymerase Chain ReactionDideoxy DNA SequencingSlide 106Slide 107Slide 108What Are the Benefits of Finding a Disease Gene?TherapyThree Types of Genetic Tests for Genetic DiseasesEthical Concerns over Genetic TestingThe Potential of Gene TherapyIntroducing Novel Alleles into Human CellsSlide 115Using Gene Therapy to Treat X-Linked Immune DeficiencySlide 117Slide 118Ethical Concerns over Gene TherapyBiotechnology in Agriculture – Golden RiceEthical ConcernsChapter 20 - GenomicsSlide 123Whole-Genome SequencingHow Are Complete Genomes Sequenced?The Shotgun Sequencing ProcessThe Role of Next-Generation Sequences StrategiesSlide 128Which Sequences Are Genes?Lateral Gene TransferEvidence for Lateral Gene TransferHow Does Lateral Gene Transfer Occur?Environmental SequencingEukaryotic GenomesRepeated Sequences and DNA FingerprintingDNA Fingerprinting ProcessSlide 137Gene FamiliesWhy Do Humans Have So Few Genes?Similarities between Human and Chimp GenomesFunctional Genomics and ProteomicsSlide 142How Are DNA Microarrays Used?Slide 144What Is Proteomics?Applied Genomics: Understanding Cancer© 2011 Pearson Education, Inc.Chapter 13 – Mendel and the Gene© 2011 Pearson Education, Inc.Introduction•In 1865, Gregor Mendel worked out the rules of inheritance through a series of brilliant experiments on garden peas.•Early in the 20th century, Walter Sutton and Theodor Boveri formulated the chromosome theory of inheritance, which proposes that meiosis causes the patterns of inheritance that Mendel observed.•Genetics is the branch of biology that focuses on inheritance.© 2011 Pearson Education, Inc.Mendel’s Experimental System•Gregor Mendel was a 19th-century monk and active member of his city’s Agricultural Society.•Mendel was interested in heredity. Heredity is the transmission of traits from parents to their offspring. A trait is any characteristic of an individual.© 2011 Pearson Education, Inc.Garden Peas: The First Model Organism in Genetics•Genetics, the branch of biology that focuses on the inheritance of traits, uses model organisms because the conclusions drawn from them can be applied to other species.•Mendel chose the common garden pea (Pisum sativum) as his model organism because:–It is easy to grow.–Its reproductive cycle is short.–It produces large numbers of seeds. –Its matings are easy to control.–Its traits are easily recognizable.© 2011 Pearson Education, Inc.How Did Mendel Arrange Matings?•Peas normally pollinate themselves, a process called self-fertilization. •Mendel could prevent this by removing the male reproductive organs containing pollen from each flower. He then used this pollen to fertilize the female reproductive organs of flowers on different plants, thus performing cross-pollination.© 2011 Pearson Education, Inc.© 2011 Pearson Education, Inc.What Traits Did Mendel Study?•Mendel worked with pea varieties that differed in seven easily recognizable traits: seed shape, seed color, pod shape, pod color, flower color, flower and pod position, and stem length. •An individual’s observable features comprise its phenotype. Mendel’s pea population had two distinct phenotypes for each of the seven traits.•Mendel worked with pure lines that produced identical offspring when self-pollinated. He used these plants to create hybrids by mating two different pure lines that differed in one or more traits.© 2011 Pearson Education, Inc.Inheritance of a Single Trait•Mendel's first experiments involved crossing pure lines that differed in just one trait. •The adults in the cross were the parental generation, the offspring are the F1 generation (for "first filial").© 2011 Pearson Education, Inc.The Monohybrid Cross•Mendel’s first experimented with crossing plants that differed in only one trait.•When Mendel crossed plants with round seeds and plants with wrinkled seeds, all of the F1 offspring had round seeds.–This contradicted the hypothesis of blending inheritance.–The genetic determinant for wrinkled seeds seemed to have disappeared.•Mendel allowed the F1 progeny to self-pollinate. –The wrinkled seed trait reappeared in the next F2 generation.© 2011 Pearson