2. Genetics

3. Do Now Hand in your Karyotyping Lab if you haven’t already! Take out the Video – What are genes question sheet? Read over the questions so you know what your looking for when your watching the video.

4. Heredity Lesson 1

5. Do Now Video: What are genes?What are genes

6. Inheritance of chromosomes Egg + sperm  zygote egg sperm zygote fertilization mitosis & development meiosis

7. Inheritance of genes On the chromosomes passed from Mom & Dad to offspring are genes –may be same information –may be different information eye color (blue or brown?) eye color (blue or brown?)

8. Effect of genes Genes come in different versions –brown vs. blue eyes –brown vs. blonde hair –alleles

9. Genes affect what you look like X BB bb Bb Where did the blue eyes go??

10. Genes affect what you look like… X Bb bb Bb bb Why did the blue eyes stay??

11. Genes affect what you look like… X Bb BB or Bb bb Where did the blue eyes come from??

12. What did we show here? Genes come in “versions” –brown vs. blue eye color –alleles Alleles are inherited separately from each parent –brown & blue eye colors are separate & do not blend either have brown or blue eyes, not a blend Some alleles mask others –brown eye color masked blue

13. How does this work? eye color (brown?) hair color eye color (blue?) Paired chromosomes have same kind of genes –but may be different alleles

14. In class assignment History and Terminology worksheet

15. Homework Determining your genes worksheet

16. Punnett Crosses Lesson 2

17. Do Now Check answers from last night’s homework (& take out last nights homework) Read over the questions on your sheet so you know what your are looking for in the video. Video: Where do your genes come from?Where do your genes come from?

18. Traits are inherited as separate units 1 from Mom 1 from Dad For each trait, an organism inherits 2 copies of a gene, 1 from each parent –a diploid organism inherits 1 set of chromosomes from each parent diploid = 2 sets of chromosomes homologous chromosomes

19. Making gametes BB= brown eyes bb= blues eyes Bb= brown eyes BBbbBbBb  brown is dominant over blue  blue is recessive to brown Remember meiosis! B B b b B b

20. How do we say it? BB= brown eyes bb= blues eyes Bb= brown eyes 2 of the same Homozygous 2 different Heterozygous BB B B bb b b BbBb B b homozygous dominant homozygous recessive

21. Punnett squares Bb x Bb male / sperm female / eggs X BB BbBbbb BbBb B b Bb

22. Genetics vs. appearance There can be a difference between how an organism looks & its genetics –appearance or trait = phenotype brown eyes vs. blue eyes –genetic makeup = genotype BB, Bb, bb 2 people can have the same appearance but have different genetics: BB vs Bb

23. Genetics vs. appearance eye color (brown) eye color (brown) eye color (blue) eye color (brown) vs. BB B B Bb B b How were these brown eyes made?

24. In class assignment Genetics Practice 1: Basic geneticsGenetics Practice 1: Basic geneticsGenetics Practice 1: Basic geneticsGenetics Practice 1: Basic genetics

25. Homework Basics Punnett SquaresBasics Punnett SquaresBasics Punnett SquaresBasics Punnett Squares

26. Penny Genetics Lesson Lesson 3 Lab Activity Lab Activity

27. 2007-2008 Genetics & The Work of Mendel Lesson 4

28. Do Now BrainPop: heredityBrainPop: heredityBrainPop: heredityBrainPop: heredity

29. Modern genetics began in the mid- 1800s in an abbey garden, where a monk named Gregor Mendel documented inheritance in peas –used good experimental design –used mathematical analysis collected data & counted them –excellent example of scientific method Gregor Mendel

30. Pollen transferred from white flower to stigma of purple flower all purple flowers result Mendel’s work ? self-pollinate Bred pea plants –cross-pollinate true breeding parents –raised seed & then observed traits –allowed offspring to self-pollinate & observed next generation

31. Mendel collected data for 7 pea traits

32. 2 nd generation 3:1 75% purple-flower peas 25% white-flower peas Looking closer at Mendel’s work Parents 100% 1 st generation (hybrids) 100% purple-flower peas X true-breeding purple-flower peas true-breeding white-flower peas self-pollinate

33. What did Mendel’s findings mean? Some traits mask others –purple & white flower colors are separate traits that do not blend purple x white ≠ light purple purple masked white –dominant allele functional protein –affects characteristic masks other alleles –recessive allele no noticeable effect allele makes a non-functioning protein homologous chromosomes allele producing functional protein mutant allele malfunctioning protein

34. Genotype vs. phenotype Difference between how an organism “looks” & its genetics –phenotype description of an organism’s trait –genotype description of an organism’s genetic makeup Explain Mendel’s results using …dominant & recessive …phenotype & genotype F1F1 P X purplewhite all purple

35. Making crosses Can represent alleles as letters –flower color alleles  P or p –true-breeding purple-flower peas  PP –true-breeding white-flower peas  pp PP x pp PpPp F1F1 P X purplewhite all purple

36. Punnett squares Pp x Pp Pp male / sperm P p female / eggs PP 75% 25% 3:1 25% 50% 25% 1:2:1 % genotype % phenotype PPPpPp PpPppp PpPp PpPp 1 st generation (hybrids) Aaaaah, phenotype & genotype can have different ratios

37. In class assignment Simple Genetics Practice Problems

38. Homework Complete simple genetics practice for homework

39. Gene Expression Lesson 5

40. Do Now Directed Reading Activity: Gene ExpressionGene Expression

41. Phenotype is controlled by both environment & genes Color of Hydrangea flowers is influenced by soil pH Human skin color is influenced by both genetics & environmental conditions Environment effect on genes Coat color in arctic fox influenced by heat sensitive alleles

42. In class assignment Gene Expression

43. Homework Regents Practice Questions

44. 2007-2008 Beyond Mendel’s Laws of Inheritance Lesson 6

45. Do Now Gregor Mendel Video: HeredityGregor Mendel Video: HeredityHeredity

46. Extending Mendelian genetics Mendel worked with a simple system –peas are genetically simple –most traits are controlled by single gene –each gene has only 2 version 1 completely dominant (A) 1 recessive (a) But its usually not that simple!

47. Incomplete dominance Hybrids have “in-between” appearance –RR = red flowers –rr = white flowers –Rr = pink flowers make 50% less color RRRrrr  RR  WW  RW

48. Incomplete dominance true-breeding red flowers true-breeding white flowers X P 100% 100% pink flowers 1 st generation (hybrids) self-pollinate 25% white 2 nd generation 25% red 1:2:1 50% pink

49. Incomplete dominance RW male / sperm R W female / eggs RR RWWW RW 25% 1:2:1 25% 50% 25% 1:2:1 % genotype % phenotype RR RW WW 25% 50% RW x RW

50. Codominance Equal dominance –human ABO blood groups –3 version A, B, i A & B alleles are codominant both A & B alleles are dominant over i allele –the genes code for different sugars on the surface of red blood cells “name tag” of red blood cell

51. Genetics of Blood type pheno- type genotype antigen on RBC antibodies in blood donation status AA A or A i type A antigens on surface of RBC anti-B antibodies __ BBB or B i type B antigens on surface of RBC anti-A antibodies __ AB both type A & type B antigens on surface of RBC no antibodies universal recipient Oi ii i no antigens on surface of RBC anti-A & anti-B antibodies universal donor

52. Blood donation clotting

53. One gene: many effects The genes that we have covered so far affect only one trait But most genes affect many traits –1 gene affects more than 1 trait dwarfism (achondroplasia) gigantism (acromegaly)

54. Many genes: one trait Polygenic inheritance –additive effects of many genes –humans skin color height weight eye color intelligence behaviors

55. Human skin color AaBbCc x AaBbCc –can produce a wide range of shades –most children = intermediate skin color –some can be very light & very dark

56. In class assignment Genetics Practice 3: Blood Types GeneticsGenetics Practice 3: Blood Types Genetics

57. Homework Finish Worksheets

58. Sex-Linked Genetics Lesson 7

59. Do Now Review Genetics Practice 3 OR practice co dominance and incomplete dominanceGenetics Practice 3practice co dominance and incomplete dominance

60. Genetics of sex Women & men are very different, but just a few genes create that difference In mammals = 2 sex chromosomes –X & Y –2 X chromosomes = female: XX –X & Y chromosome = male: XY XY XX

61. Sex chromosomes

62. Sex-linked traits Sex chromosomes have other genes on them, too –especially the X chromosome –hemophilia in humans blood doesn’t clot –Duchenne muscular dystrophy in humans loss of muscle control –red-green color blindness see green & red as shades of grey XY XX

63. Sex-linked traits XHXH Y male / sperm XHXH XhXh female / eggs XHXHXHXH XHXhXHXh XHYXHYXhYXhY XHXhXHXh XHXH XhXh XHYXHY Y XHXH XHXHXHXH XHYXHY XHXhXHXh XhYXhY sex-linked recessive 2 normal parents, but mother is carrier HH Hh x XHYXHY XHXhXHXh

66. Dominant ≠ most common allele Polydactyly dominant allele Because an allele is dominant does not mean… –it is better, or –it is more common

67. Polydactyly recessive allele far more common than dominant  only 1 individual out of 500 has more than 5 fingers/toes  so 499 out of 500 people are homozygous recessive (aa) the allele for >5 fingers/toes is DOMINANT & the allele for 5 digits is recessive individuals are born with extra fingers or toes

68. In class assignment genetics_xlinked

69. Homework X-Linked Worksheet

70. Variations on a Human Face Variations Lab