1. Copyright © 2009 Pearson Education, Inc. PowerPoint Lectures for Biology: Concepts & Connections, Sixth Edition Campbell, Reece, Taylor, Simon, and Dickey Chapter 9 Patterns of Inheritance Lecture by Mary C. Colavito

2. 5/11/11 – “C” Day  Objective: To explore how traits are inherited  Do Now: What is a “pure bred”? What is a “wild- type”?  Today: - Notes on Mendel and Monohybrid Crosses - Bikini Bottom Genetics  NO STUDY HALL TOMORROW  Copyright © 2009 Pearson Education, Inc.

3. 5/12/11 – “D” Day  Objective: To explore how traits are inherited  Do Now: What is the phenotypic ratio when a hybrid tall plant is crossed with a short plant. Show a punnett square to support your answer.  Today: - Reebop Genetics - HW - Bikini Bottom Genetics  NO STUDY HALL TODAY  Copyright © 2009 Pearson Education, Inc.

4. 5/13/11 – “E” Day  Objective: To explore how traits are inherited  Do Now: Get out Reebop Genetics – turn to page 7  Today: - Complete Reebop Genetics - Bloodtyping Lab - HW Complete Bikini Bottom Genetics - Exercises 3 – 6 in yellow packet  PJAS this weekend, no Mrs. P on Monday – you will be “making babies” Copyright © 2009 Pearson Education, Inc.

5. 5/18/11 – “F” Day  Objective: To explore how traits are inherited  Do Now: A mother who has A blood has a child with a man who has B blood. Can they have a child with O blood? Show a punnett square to support your answer.  Today: - Complete your “babies” and turn in - Turn in bloodtyping lab and bikini bottom genetics - Work on Pedigree Packets – Questions 1 – 11 due tomorrow - We will finish “Clone” tomorrow Copyright © 2009 Pearson Education, Inc.

6. 5/19/11 – “B” Day  Objective: To explore how traits are inherited  Do Now: A blue reebop and a yellow reebop have babies. If this trait is inherited codominantly what would the offspring look like? Incomplete dominantly?  Today: - Check in Ex. 3 - 6 - Complete notes - “Clone” Copyright © 2009 Pearson Education, Inc.

7. 5/20/11 – “C” Day  Objective: To explore how traits are inherited  Do Now: What is plieotropy? What is epistasis?  Today: - Collect Pedigrees - Complete notes - Start Sex-linked traits - Finish “Clone” - Start “Click and Clone”  HW – complete sex linked traits Copyright © 2009 Pearson Education, Inc.

8. HOMEWORK  Complete Bikini Bottom Genetics  Exercises 3 – 6 in yellow packet  Bloodtyping Lab  ALL DUE WEDNESDAY

9. MENDEL’S LAWS Copyright © 2009 Pearson Education, Inc.

10. 9.1 The science of genetics has ancient roots  Pangenesis was an early explanation for inheritance –It was proposed by Hippocrates –Particles called pangenes came from all parts of the organism to be incorporated into eggs or sperm –Characteristics acquired during the parents’ lifetime could be transferred to the offspring –Aristotle rejected pangenesis and argued that instead of particles, the potential to produce the traits was inherited  Blending was another idea, based on plant breeding –Hereditary material from parents mixes together to form an intermediate trait, like mixing paint Copyright © 2009 Pearson Education, Inc.

11. 9.2 Experimental genetics began in an abbey garden  Gregor Mendel discovered principles of genetics in experiments with the garden pea –Mendel showed that parents pass heritable factors to offspring (heritable factors are now called genes) –Advantages of using pea plants –Controlled matings –Self-fertilization or cross-fertilization –Observable characteristics with two distinct forms –True-breeding strains Copyright © 2009 Pearson Education, Inc.

13. Petal Stamen Carpel

14. Sepals – the leaf like structures that surround the flower Petals – Attract insects and other pollinators Carpel(s) – are fused together to form a structure called the Pistil Stigma – at the top of the pistil, sticky for pollen (sperm) to attach Style - the long tube that attaches stigma to the ovary Ovules (eggs) are stored in the ovary until they are fertilized Stamen are the male reproductive organs the anther produces the pollen (sperm) ANGIOSPERM (fruiting and flowering plant) Anatomy

15. Transferred pollen from stamens of white flower to carpel of purple flower Stamens Carpel Parents (P) Purple 2 White Removed stamens from purple flower 1

16. Transferred pollen from stamens of white flower to carpel of purple flower Stamens Carpel Parents (P) Purple 2 White Removed stamens from purple flower 1 Pollinated carpel matured into pod 3

17. Transferred pollen from stamens of white flower to carpel of purple flower Stamens Carpel Parents (P) Purple 2 White Removed stamens from purple flower 1 Pollinated carpel matured into pod 3 Offspring (F 1 ) Planted seeds from pod 4

18. Flower color White Axial Purple Flower positionTerminal Yellow Seed color Green Round Seed shapeWrinkled Inflated Pod shape Constricted Green Pod colorYellow Tall Stem lengthDwarf

19. 9.3 Mendel’s law of segregation describes the inheritance of a single character  Example of a monohybrid cross –Parental generation: purple flowers  white flowers –F 1 generation: all plants with purple flowers –F 2 generation: of plants with purple flowers of plants with white flowers  Mendel needed to explain –Why one trait seemed to disappear in the F 1 generation –Why that trait reappeared in one quarter of the F 2 offspring Copyright © 2009 Pearson Education, Inc.

20. P generation (true-breeding parents) Purple flowers White flowers

21. P generation (true-breeding parents) Purple flowers White flowers F 1 generation All plants have purple flowers

22. P generation (true-breeding parents) Purple flowers White flowers F 1 generation All plants have purple flowers F 2 generation Fertilization among F 1 plants (F 1  F 1 ) of plants have purple flowers 3–43–4 of plants have white flowers 1–41–4

23. 9.3 Mendel’s law of segregation describes the inheritance of a single character  Four Hypotheses 1.Genes are found in alternative versions called alleles; a genotype is the listing of alleles an individual carries for a specific gene 2.For each characteristic, an organism inherits two alleles, one from each parent; the alleles can be the same or different –A homozygous genotype has identical alleles –A heterozygous genotype has two different alleles Copyright © 2009 Pearson Education, Inc.

24. 9.3 Mendel’s law of segregation describes the inheritance of a single character  Four Hypotheses 3.If the alleles differ, the dominant allele determines the organism’s appearance, and the recessive allele has no noticeable effect –The phenotype is the appearance or expression of a trait –The same phenotype may be determined by more than one genotype –Law of segregation: Allele pairs separate (segregate) from each other during the production of gametes so that a sperm or egg carries only one allele for each gene Copyright © 2009 Pearson Education, Inc.

25. P plants 1–21–2 1–21–2 Genotypic ratio 1 PP : 2 Pp : 1 pp Phenotypic ratio 3 purple : 1 white F 1 plants (hybrids) Gametes Genetic makeup (alleles) All All Pp Sperm Eggs PP p ppPp P p P p P P p PP pp All Gametes F 2 plants

26. 9.4 Homologous chromosomes bear the alleles for each character  For a pair of homologous chromosomes, alleles of a gene reside at the same locus –Homozygous individuals have the same allele on both homologues –Heterozygous individuals have a different allele on each homologue Copyright © 2009 Pearson Education, Inc.

27. Gene loci Homozygous for the dominant allele Dominant allele Homozygous for the recessive allele Heterozygous Recessive allele Genotype: P B a P PP a aa b Bb

28. 9.5 The law of independent assortment is revealed by tracking two characters at once  Example of a dihybrid cross –Parental generation: round yellow seeds  wrinkled green seeds –F 1 generation: all plants with round yellow seeds –F 2 generation: of plants with round yellow seeds of plants with round green seeds of plants with wrinkled yellow seeds of plants with wrinkled green seeds  Mendel needed to explain –Why nonparental combinations were observed –Why a 9:3:3:1 ratio was observed among the F 2 offspring Copyright © 2009 Pearson Education, Inc.

29. 9.5 The law of independent assortment is revealed by tracking two characters at once  Law of independent assortment –Each pair of alleles segregates independently of the other pairs of alleles during gamete formation –For genotype RrYy, four gamete types are possible: RY, Ry, rY, and ry Copyright © 2009 Pearson Education, Inc.

30. P generation 1–21–2 Hypothesis: Dependent assortment Hypothesis: Independent assortment 1–21–2 1–21–2 1–21–2 1–41–4 1–41–4 1–41–4 1–41–4 1–41–4 1–41–4 1–41–4 1–41–4 9 –– 16 3 –– 16 3 –– 16 1 –– 16 RRYY Gametes Eggs F 1 generation Sperm F 2 generation Eggs Gametes rryy RrYy ry RY ry RY ry RY Hypothesized (not actually seen) Actual results (support hypothesis) RRYY rryy RrYy ry RY RRYY rryy RrYy ry RY RrYy rrYYRrYY RRYyRrYY RRYy rrYy Rryy RRyy rY Ry ry Yellow round Green round Green wrinkled Yellow wrinkled RY rY Ry

31. Phenotypes Genotypes Mating of heterozygotes (black, normal vision) Phenotypic ratio of offspring Black coat, normal vision B_N_ 9 black coat, normal vision Black coat, blind (PRA) B_nn 3 black coat, blind (PRA) Chocolate coat, normal vision bbN_ 3 chocolate coat, normal vision Chocolate coat, blind (PRA) bbnn 1 chocolate coat, blind (PRA) Blind BbNn

32. 9.6 Geneticists use the testcross to determine unknown genotypes  Testcross –Mating between an individual of unknown genotype and a homozygous recessive individual –Will show whether the unknown genotype includes a recessive allele –Used by Mendel to confirm true-breeding genotypes Copyright © 2009 Pearson Education, Inc.

33. B_ or Two possibilities for the black dog: Testcross: Genotypes Gametes Offspring1 black : 1 chocolate All black Bb bb BB Bbbb B b Bb b b B

34. 9.7 Mendel’s laws reflect the rules of probability  The probability of a specific event is the number of ways that event can occur out of the total possible outcomes.  Rule of multiplication –Multiply the probabilities of events that must occur together  Rule of addition –Add probabilities of events that can happen in alternate ways Copyright © 2009 Pearson Education, Inc.

35. F 1 genotypes 1–21–2 1–21–2 1–21–2 1–21–2 1–41–4 1–41–4 1–41–4 1–41–4 Formation of eggs Bb female F 2 genotypes Formation of sperm Bb male B B B B B B b b b bb b

36. Freckles Widow’s peak Free earlobe No freckles Straight hairline Attached earlobe Dominant Traits Recessive Traits

37. FrecklesNo freckles

38. Widow’s peak Straight hairline

39. Free earlobeAttached earlobe

40. 9.8 CONNECTION: Genetic traits in humans can be tracked through family pedigrees  A pedigree –Shows the inheritance of a trait in a family through multiple generations –Demonstrates dominant or recessive inheritance –Can also be used to deduce genotypes of family members Copyright © 2009 Pearson Education, Inc.

41. Ff FemaleMale Affected Unaffected First generation (grandparents) Second generation (parents, aunts, and uncles) Third generation (two sisters) Ff ff FF or

42. VARIATIONS ON MENDEL’S LAWS Copyright © 2009 Pearson Education, Inc.

43. 9.11 Incomplete dominance results in intermediate phenotypes  Incomplete dominance –Neither allele is dominant over the other –Expression of both alleles is observed as an intermediate phenotype in the heterozygous individual Copyright © 2009 Pearson Education, Inc.

44. P generation 1–21–2 1–21–2 1–21–2 1–21–2 1–21–2 1–21–2 F 1 generation F 2 generation Red RR Gametes Eggs Sperm RR rR Rrrr R r R r R r Pink Rr R r White rr

45. HH Homozygous for ability to make LDL receptors hh Homozygous for inability to make LDL receptors Hh Heterozygous LDL receptor LDL Cell Normal Mild disease Severe disease Genotypes: Phenotypes: Incomplete dominance of hypercholesterolemia

46. 9.12 Many genes have more than two alleles in the population  Multiple alleles –More than two alleles are found in the population –A diploid individual can carry any two of these alleles –The ABO blood group has three alleles, leading to four phenotypes: type A, type B, type AB, and type O blood Copyright © 2009 Pearson Education, Inc.

47. 9.12 Many genes have more than two alleles in the population  Codominance –Neither allele is dominant over the other –Expression of both alleles is observed as a distinct phenotype in the heterozygous individual –Observed for type AB blood Copyright © 2009 Pearson Education, Inc.

48. Blood Group (Phenotype) Genotypes O A ii I A or I A i Red Blood Cells Carbohydrate A Antibodies Present in Blood Anti-A Anti-B Reaction When Blood from Groups Below Is Mixed with Antibodies from Groups at Left Anti-B O AB AB B I B or I B i Carbohydrate B AB IAIBIAIB — Anti-A

49. Blood Group (Phenotype) Genotypes O A ii I A or I A i Red Blood Cells Carbohydrate A B I B or I B i Carbohydrate B AB IAIBIAIB

50. Antibodies Present in Blood Anti-A Anti-B Reaction When Blood from Groups Below Is Mixed with Antibodies from Groups at Left Anti-B O A B AB — Anti-A Blood Group (Phenotype) O A B AB

51. 9.13 A single gene may affect many phenotypic characters  Pleiotropy –One gene influencing many characteristics –The gene for sickle cell disease –Affects the type of hemoglobin produced –Affects the shape of red blood cells –Causes anemia –Causes organ damage –Is related to susceptibility to malaria Copyright © 2009 Pearson Education, Inc.

52. Clumping of cells and clogging of small blood vessels Pneumonia and other infections Accumulation of sickled cells in spleen Pain and fever Rheumatism Heart failure Damage to other organs Brain damage Spleen damage Kidney failure Anemia Paralysis Impaired mental function Physical weakness Breakdown of red blood cells Individual homozygous for sickle-cell allele Sickle cells Sickle-cell (abnormal) hemoglobin Abnormal hemoglobin crystallizes, causing red blood cells to become sickle-shaped

53. 9.14 A single character may be influenced by many genes  Polygenic inheritance –Many genes influence one trait –Skin color is affected by at least three genes Copyright © 2009 Pearson Education, Inc.

54. P generation 1–81–8 F 1 generation F 2 generation Fraction of population Skin color Eggs Sperm 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 aabbcc (very light) AABBCC (very dark) AaBbCc 1 –– 64 15 –– 64 6 –– 64 1 –– 64 15 –– 64 6 –– 64 20 –– 64 1 –– 64 15 –– 64 6 –– 64 20 –– 64

55. P generation 1–81–8 F 1 generation F 2 generation Eggs Sperm 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 1–81–8 aabbcc (very light) AABBCC (very dark) AaBbCc 1 –– 64 15 –– 64 6 –– 64 1 –– 64 15 –– 64 6 –– 64 20 –– 64

56. Fraction of population Skin color 1 –– 64 15 –– 64 6 –– 64 20 –– 64

57. Epistatic Traits  Epistasis is where the effects of one gene are modified by one or several other genes, which are sometimes called modifier genes.  For example, the gene causing albinism would hide the gene controlling color of a person's hair.

58.  In horses, brown coat color (B) is dominant over tan (b).  Gene expression is dependent on a second gene that controls the deposition of pigment in hair. The dominant gene (C) codes for the presence of pigment in hair, the recessive gene (c) codes for the absence of pigment.

59. 9.15 The environment affects many characters  Phenotypic variations are influenced by the environment –Skin color is affected by exposure to sunlight –Susceptibility to diseases, such as cancer, has hereditary and environmental components Copyright © 2009 Pearson Education, Inc.

61.  Which one is Mrs. P?

62. THE CHROMOSOMAL BASIS OF INHERITANCE (This should be review…) Copyright © 2009 Pearson Education, Inc.

63. 9.16 Chromosome behavior accounts for Mendel’s laws  Mendel’s Laws correlate with chromosome separation in meiosis –The law of segregation depends on separation of homologous chromosomes in anaphase I –The law of independent assortment depends on alternative orientations of chromosomes in metaphase I Copyright © 2009 Pearson Education, Inc.

64. F 1 generation R Metaphase I of meiosis (alternative arrangements) r Y y R r Y y R r Y y All round yellow seeds (RrYy)

65. F 1 generation R Metaphase I of meiosis (alternative arrangements) r Y y R r Y y R r Y y All round yellow seeds (RrYy) Anaphase I of meiosis Metaphase II of meiosis R y r Y r y R Y R r Y y R r Y y

66. F 1 generation R Metaphase I of meiosis (alternative arrangements) r Y y R r Y y R r Y y All round yellow seeds (RrYy) Anaphase I of meiosis Metaphase II of meiosis R y r Y r y R Y R r Y y R r Y y 1–41–4 R y Ry R y r Y 1–41–4 rY r Y 1–41–4 ry r y 1–41–4 RY R Y R Y Gametes Fertilization among the F 1 plants :3 9 :1 F 2 generation r y

67. 9.17 Genes on the same chromosome tend to be inherited together  Linked Genes –Are located close together on the same chromosome –Tend to be inherited together  Example studied by Bateson and Punnett –Parental generation: plants with purple flowers, long pollen crossed to plants with red flowers, round pollen –The F 2 generation did not show a 9:3:3:1 ratio –Most F 2 individuals had purple flowers, long pollen or red flowers, round pollen Copyright © 2009 Pearson Education, Inc.

68. Purple long Purple round Red long Red round Explanation: linked genes Parental diploid cell PpLl Experiment Purple flower PpLl Long pollen PpLl Prediction (9:3:3:1) Observed offspring Phenotypes 284 21 55 215 71 24 Most gametes Meiosis PL pl PL pl Fertilization Sperm Most offspring Eggs 3 purple long : 1 red round Not accounted for: purple round and red long PL pl PL pl

69. Purple long Purple round Red long Red round Experiment Purple flower PpLl Long pollen PpLl Prediction (9:3:3:1) Observed offspring Phenotypes 284 21 55 215 71 24

70. Explanation: linked genes Parental diploid cell PpLl Most gametes Meiosis PL pl PL pl Fertilization Sperm Most offspring Eggs 3 purple long : 1 red round Not accounted for: purple round and red long PL pl PL pl

71. 9.18 Crossing over produces new combinations of alleles  Linked alleles can be separated by crossing over –Recombinant chromosomes are formed –Thomas Hunt Morgan demonstrated this in early experiments –Geneticists measure genetic distance by recombination frequency Copyright © 2009 Pearson Education, Inc.

72. Gametes Tetrad Crossing over Baba a b A B A B A b

74. Experiment Parental phenotypes Recombination frequency = Black vestigial Black body, vestigial wings GgLl Offspring FemaleMale Gray long 965 944 206 185 ggll Gray vestigial Black long Gray body, long wings (wild type) Recombinant phenotypes 391 recombinants 2,300 total offspring Explanation = 0.17 or 17% G L g l GgLl (female) ggll (male) G L g l g L g l G L Sperm Eggs Offspring g L G l

75. Experiment Parental phenotypes Recombination frequency = Black vestigial Black body, vestigial wings GgLl Offspring Female Male Gray long 965 944206 185 ggll Gray vestigial Black long Gray body, long wings (wild type) Recombinant phenotypes 391 recombinants 2,300 total offspring = 0.17 or 17%

76. Explanation G L g l GgLl (female) ggll (male) G L g l g L g l G L Sperm Eggs Offspring g L G l

77. 9.19 Geneticists use crossover data to map genes  Genetic maps –Show the order of genes on chromosomes –Arrange genes into linkage groups representing individual chromosomes Copyright © 2009 Pearson Education, Inc.

78. Chromosome 9.5% Recombination frequencies 9% 17% g c l

79. Mutant phenotypes Short aristae Black body (g) Cinnabar eyes (c) Vestigial wings (l) Brown eyes Long aristae (appendages on head) Gray body (G) Red eyes (C) Normal wings (L) Red eyes Wild-type phenotypes

80. SEX CHROMOSOMES AND SEX-LINKED GENES Copyright © 2009 Pearson Education, Inc.

81. 9.20 Chromosomes determine sex in many species  X-Y system in mammals, fruit flies –XX = female; XY = male  X-O system in grasshoppers and roaches –XX = female; XO = male  Z-W in system in birds, butterflies, and some fishes –ZW = female, ZZ = male  Chromosome number in ants and bees –Diploid = female; haploid = male Copyright © 2009 Pearson Education, Inc.

82. X Y

83. (male) Sperm (female) 44 + XY Parents’ diploid cells 44 + XX 22 + X 22 + Y 22 + X 44 + XY 44 + XX Egg Offspring (diploid)

84. 22 + X 22 + XX

85. 76 + ZZ 76 + ZW

86. 16 32

87.  Sex-linked genes are located on either of the sex chromosomes –Reciprocal crosses show different results –White-eyed female  red-eyed male red-eyed females and white-eyed males –Red-eyed female  white-eyed male red-eyed females and red-eyed males –X-linked genes are passed from mother to son and mother to daughter –X-linked genes are passed from father to daughter –Y-linked genes are passed from father to son 9.21 Sex-linked genes exhibit a unique pattern of inheritance Copyright © 2009 Pearson Education, Inc.

89. Female Male X R X r Y X R Y X R X r Y XrXr XRXR Sperm Eggs R = red-eye allele r = white-eye allele

90. Female Male X R X r X R Y X R Y XRXR XRXR Sperm Eggs X r X R X r Y XrXr

91. Female Male X R X r X r Y X R Y X R Y XrXr XRXR Sperm Eggs X r X r Y XrXr

92. 9.22 CONNECTION: Sex-linked disorders affect mostly males  Males express X-linked disorders such as the following when recessive alleles are present in one copy –Hemophilia –Colorblindness –Duchenne muscular dystrophy Copyright © 2009 Pearson Education, Inc.

93. Queen Victoria Albert Alice Louis Alexandra Czar Nicholas II of Russia Alexis

94. 9.23 EVOLUTION CONNECTION: The Y chromosome provides clues about human male evolution  Similarities in Y chromosome sequences –Show a significant percentage of men related to the same male parent –Demonstrate a connection between people living in distant locations Copyright © 2009 Pearson Education, Inc.

95. Homologous chromosomes Alleles, residing at the same locus Meiosis Gamete from other parent Fertilization Diploid zygote (containing paired alleles) Paired alleles, alternate forms of a gene Haploid gametes (allele pairs separate)

96. Incomplete dominance Red RR Single gene Single characters (such as skin color) Multiple characters Pleiotropy Polygenic inheritance Multiple genes White rr Pink Rr

97. Genes located on (b) (a) at specific locations called alternative versions called if both same, genotype called expressed allele called inheritance when phenotype In between called unexpressed allele called if different, genotype called chromosomes heterozygous (d) (c) (f) (e)

99. 1.Explain and apply Mendel’s laws of segregation and independent assortment 2.Distinguish between terms in the following groups: allele—gene; dominant—recessive; genotype—phenotype; F 1 —F 2 ; heterozygous— homozygous; incomplete dominance— codominance 3.Explain the meaning of the terms locus, multiple alleles, pedigree, pleiotropy, polygenic inheritance You should now be able to Copyright © 2009 Pearson Education, Inc.

100. 4.Describe the difference in inheritance patterns for linked genes and explain how recombination can be used to estimate gene distances 5.Describe how sex is inherited in humans and identify the pattern of inheritance observed for sex-linked genes 6.Solve genetics problems involving monohybrid and dihybrid crosses for autosomal and sex- linked traits, with variations on Mendel’s laws You should now be able to Copyright © 2009 Pearson Education, Inc.