Mendel And Punnett Squares - Loudoun County Public
biologySlide1 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor Mendel11-1 The Work of Gregor MendelSlide2 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelGregor Mendel’s PeasGregor Mendel’s PeasGenetics is the scientific study of heredity.Gregor Mendel was an Austrian monk. His workwas important to the understanding of heredity.Mendel carried out his work with ordinary gardenpeas.Slide3 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelGregor Mendel’s PeasMendel knew that the male part ofeach flowerproduces pollen,(containingsperm). the female partof the flowerproduces eggcells.Slide4 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelGregor Mendel’s PeasDuring sexual reproduction, sperm and egg cells joinin a process called fertilization.Fertilization produces a new cell.Pea flowers are self-pollinating.Slide5 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelGregor Mendel’s PeasMendel had true-breeding pea plants that, if allowedto self-pollinate, would produce offspring identical tothemselves.Cross-pollinationMendel was able toproduce seeds thathad two differentparents.Slide6 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelNotes What is Genetics?Study of inheritance. Who is Gregor Mendel?Scientists who studied inheritance in pea plants.Why did he study pea plants?He knew that there were male and female parts onthe plants. He also knew they could self pollinateor cross pollinate.Slide7 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelGenes and DominanceGenes and DominanceA trait is a specific characteristic that varies fromone individual to another.Mendel studied seven pea plant traits, each with twocontrasting characters.He crossed plants with each of the sevencontrasting characters and studied their offspring.Slide8 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelGenes and DominanceMendel’s Seven F1 Crosses on Pea PlantsMendel’s F1 Crosses on Pea PlantsSlide9 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelGenes and DominanceEach original pair of plants is the P (parental)generation.The offspring are called the F1, or “first filial,”generation.The offspring of crosses between parents with differenttraits are called hybrids.Slide10 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelSegregationMendel's F2 GenerationP GenerationTallShortF2 GenerationF1 GenerationTallTallTallTallTallShortSlide11 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelGenerationsGenotypePhenotypeNOTESPunnett Square ExampleParentF1F2Slide12 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelGenes and DominanceMendel's Conclusions:1. Principle of Independent Assortment:Traits do not pass together.Example: Yellow wrinkled or Green wrinkled2. Principle of Dominance:Some alleles are dominant while others are recessive.Dominant always shows over recessive trait.3. Principle of Segregation:Traits separate during the formation of gametes. Meiosis!Slide13 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelSegregationAlleles separate during gamete formation.Slide14 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelGenetics and ProbabilityGenetics and ProbabilityProbability The likelihood that a particularevent will occur.The principles of probability can be used topredict the outcomes of genetic crosses.Slide15 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelPunnett SquaresPunnett SquaresPunnett square The gene combinations thatmight result from a genetic cross can bedetermined by drawing a diagram.Punnett squares can be used to predict andcompare the genetic variations that will resultfrom a cross.Slide16 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelNotes Let’s go to your notes to look at human genotypesand phenotypes. Then work on Punnett Square ExamplesSlide17 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelNOTESREMEMBER from your vocabulary: Homozygous – Heterozygous – Phenotype – Genotype –Slide18 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelNOTESMonohybrid Cross ExamplesGenotypesPhenotypesSlide19 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelNOTESMonohybrid Cross ExamplesGenotypesPhenotypesSlide20 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelNOTESMonohybrid Cross ExamplesGenotypesPhenotypesSlide21 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelIndependent AssortmentIndependent AssortmentTo determine if the segregation of one pair ofalleles affects the segregation of another pair ofalleles, Mendel performed a two-factor cross.Slide22 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelIndependent AssortmentThe alleles for round (R) andyellow (Y) are dominant overthe alleles for wrinkled (r) andgreen (y).The Punnett square predicts a9 : 3 : 3 :1 ratio in the F2generation.Slide23 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelIndependent AssortmentThe Punnett square predicts a 9 : 3 : 3 :1 ratio in theF2 generation.Represents:Independent AssortmentSlide24 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelIndependent Assortment Dimples and the ability to roll your tongue are both dominant traits.Cross a man who is heterozygous for dimples and cannot roll his tonguewith a woman who does not have dimples but is homozygous dominantfor tongue rolling. Key: Cross:Slide25 of 32Copyright Pearson Prentice HallEnd Show
11–3 Exploring Mendelian GeneticsBeyond Dominant andRecessive AllelesIncomplete DominanceWhen one allele is not completely dominant overanother it is called incomplete dominance.In incomplete dominance, the heterozygousphenotype is between the two homozygousphenotypes.BLEND – RED WHITE PinkSlide26 of 31Copyright Pearson Prentice HallEnd Show
11–3 Exploring Mendelian GeneticsBeyond Dominant andRecessive AllelesRRA cross betweenred (RR) andwhite (WW) fouro’clock plantsproduces pinkcolored flowers(RW).WWSlide27 of 31Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelIncomplete dominance Try to cross 2 pink snapdragons. Cross:Slide28 of 32Copyright Pearson Prentice HallEnd Show
11–3 Exploring Mendelian GeneticsCodominanceCodominanceIn codominance, both alleles contribute to thephenotype.BOTH SHOW BLACK WHITE SPECKLEDIn certain varieties of chicken, the allele for blackfeathers is codominant with the allele for whitefeathers.Heterozygous chickens are speckled with bothblack and white feathers. The black and whitecolors do not blend to form a new color, but appearseparately.Slide29 of 31Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelCodominance A black cat crossed with an orange one results in astriped condition know as tortoise-shell. If twotortoise-shell cats should mate, what would be thegenotypic and phenotypic outcome? Key:Slide30 of 32Copyright Pearson Prentice HallEnd Show
11–3 Exploring Mendelian GeneticsMultiple AllelesMultiple AllelesGenes that are controlled by more than two allelesare said to have multiple alleles.An individual can’t have more than two alleles.However, more than two possible alleles can existin a population.A rabbit's coat color is determined by a single genethat has at least four different alleles.Slide31 of 31Copyright Pearson Prentice HallEnd Show
11–3 Exploring Mendelian GeneticsSlide32 of 31End Show
11-1 The Work of Gregor MendelMultiple Alleles A man with blood type AB marries a woman withblood type O. Work out the possible blood types oftheir offspring. Cross: IA IB x iiSlide33 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelMultiple Alleles Work out the possible blood types of the offspringaccording to a cross between a parent who is AOand BO Blood. Cross: IAi x IBiSlide34 of 32Copyright Pearson Prentice HallEnd Show
14–2 Human ChromosomesSex-Linked GenesSex-Linked GenesThe X chromosome and the Y chromosomesdetermine sex.Genes located on these chromosomes are calledsex-linked genes.More than 100 sex-linked genetic disorders havenow been mapped to the X chromosome.Slide35 of 25Copyright Pearson Prentice HallEnd Show
14–2 Human ChromosomesSex-Linked GenesPossible Inheritance ofColorblindness AlleleSlide36 of 25Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelSex Linked Crosses Eye color is a sex-linked trait in fruit flies carried on the X chromosome– R for dominant red and r for white. Determine the sex and eye colorfor a father who has white eyes and mother who is homozygousdominate for red eyes. Cross:Slide37 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelMultiple Alleles Hemophilia is a recessive sex linked disorder that is carried on the Xchromosome - h for hemophilia and H for normal blood clotting. Cross afather who has hemophilia with a mother who is a carrier (heterozygous)for the disease, but does not show symptoms for hemophilia. Cross:Slide38 of 32Copyright Pearson Prentice HallEnd Show
11-1 The Work of Gregor MendelLab ProblemsPunnett Squares LabREMEMBER – Use the examples we just created in class to help youcomplete the lab problems.Lab problems will be due at the end of class on Wednesday Feb 21.Slide39 of 32Copyright Pearson Prentice HallEnd Show
11-1Click to Launch:Continue to:- or -Slide40 of 32End ShowCopyright Pearson Prentice Hall
11-1Gametes are also known asa. genes.b. sex cells.c. alleles.d. hybrids.Slide41 of 32End ShowCopyright Pearson Prentice Hall
11-1The offspring of crosses between parents withdifferent traits are calleda. alleles.b. hybrids.c. gametes.d. dominant.Slide42 of 32End ShowCopyright Pearson Prentice Hall
11-1In Mendel’s pea experiments, the male gametesare thea. eggs.b. seeds.c. pollen.d. sperm.Slide43 of 32End ShowCopyright Pearson Prentice Hall
11-1In a cross of a true-breeding tall pea plant with atrue-breeding short pea plant, the F1 generationconsists ofa. all short plants.b. all tall plants.c. half tall plants and half short plants.d. all plants of intermediate height.Slide44 of 32End ShowCopyright Pearson Prentice Hall
11-1If a particular form of a trait is always presentwhen the allele controlling it is present, then theallele must bea. mixed.b. recessive.c. hybrid.d. dominant.Slide45 of 32End ShowCopyright Pearson Prentice Hall
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The Punnett square predicts a 9 : 3 : 3 :1 ratio in the F 2 generation. Represents: Independent Assortment. End Show 11-1 The Work of Gregor Mendel Slide 25 of 32 . Eye color is a sex-linked trait in fruit flies carried on the X chromosome –R for dominant red and r for white. Determine the sex and eye color
Practice with Punnett Squares Pilot Condition P This worksheet covers the basics of Mendelian inheritance and Punnett squares. Practice problems, featuring traits from the Mutt Mixer interactive, give students a chance to apply each new idea. By the end, students should be able to fill in a Punnett
Using Punnett Squares . One of the best ways to predict the outcome of a genetic cross is by drawing a simple diagram known as a . Punnett square. Punnett squares allow you to predict the genotype and phenotype combinations in genetic crosses using mathematical probability.
Punnett squares The probability the next generation will exhibit a certain trait can be shown with a Punnett square. The genotype of the mother is shown on the top of the square (TT) The genotype of the father is shown on the side of the square (tt) The various combinations of genes (genotypes) are shown in the squares. All of
Punnett Squares for Two-Factor or Dihybrid Cross - When two traits are being considered, Punnett square will need _ squares. - Each parent will pass one allele of each gene pair to the offspring o Example, a parent with AaBb could pass 4 allele combinations on to their offspring AB, Ab, aB, ab 3.
Gregor Mendel's Peas The work of an Austrian monk named Gregor Mendel, shown in Figure 11-1, was particularly important to understanding biological inheritance. Gregor Mendel was born in 1822 in what is now the Czech Republic. After becoming a priest, Mendel spent several years stud
3. A Punnett square is a visual representation of the relative probabilities of offspring outcomes, for both gene combinations and visible traits. KEY VOCABULARY allele heterozygous carrier Punnett square dominant recessive homozygous MATERIALS AND ADVANCE PREPARATION For each student 1 Student Sheet 61.1, “Punnett Squares—Step by Step”
Complete the Punnett squares based on the information in the pictures, and then answer the questions to the right of each Punnett square. Gray fur have a homozygous recessive genotype? White eyes Gg gg 1. What percentage of the offspring will _ 2. What will be the ratio of gray fur to white fur in the offspring? _ Punnett Squares .
“Accounting is the art of recording, classifying and summarizing in a significant manner and in terms of money, transactions and events which are, in part at least, of a financial character, and interpreting the result thereof”. Definition by the American Accounting Association (Year 1966): “The process of identifying, measuring and communicating economic information to permit informed .
