1. “The Father of Genetics” Austrian Monk during the 19 th century (1822-1884) Studied Pea plants https://www.youtube.com/watch?v=GTiOETaZg4w

2. Peas were good choice. – Readily available – Easy to self-pollinate and cross-pollinate Good experimental choices. – Only chose “either-or” traits (purple OR white) – Started with true-breeding (purebred) plants – Followed for 3 generations (P, F 1, F 2 ) Kept good quantitative data. – Very large sample sizes

3.  Cross-pollinate 2 purebred plants (P generation)  Resulting offspring (F 1 generation) were all with dominant trait

4. So where did the “white” go? Mendel allowed F1 plants to self-pollinate to see if they really had “lost” the white

5. Approximately ¾ of F 1 plants produced seeds that grew into purple flower plants The remaining ¼ made white flower plants

7. Alternate versions of hereditary “factors” account for variation in inherited traits For each trait, an organism inherits 2 “factors” (one from each parent)

8.  If the “factors” differ, one is dominant and other is recessive  The 2 “factors” for each trait separate during gamete production (meiosis) Law of segregation - when sex cells are made… the 2 factors separate…1 per gamete

9. Mathematically proven through both generations

10.  Allele pairs separate independently during the formation of gametes. Traits are transmitted to the offspring independently of one another

11.  Genotype Combination of genes (ex: Tt)  Phenotype traits (ex: tall)  Homozygous Two of same allele (ex: TT or tt)  Heterozygous One of each allele (ex: Tt)  Dominant Gets expressed; use capital letter  Recessive Gets covered; use lowercase letter

12.  Where are the “factors” that Mendel discovered? On our chromosomes  How do these “factors” get passed on to offspring? Through the gametes during fertilization  What do we call these “factors” now? Alleles (different forms of the same genes)

13.  Why can’t we use mitosis to make gametes? Mitosis makes diploid cells with two sets of chromosomes (2n = diploid) * gametes must be haploid (n) having only one set of chromosomes  What is the main goal of meiosis? Meiosis produces cells with only one set of chromosomes which are haploid gametes

14.  Father genotypes always goes on top  Mother genotypes always goes on the side  Practice on your sheet! This is a monohybrid  1 st square: AA x aa  2 nd square: PP x pp List genotypes & phenotypes List types of alleles  Homozygous  Heterozygous

15.  Crosses can be larger then the simple 4 square- this is called a dihybrid Some you may see as: AaBb x AaBb When you cross this, you should “cross multiply” each individual by itself… i.e. (Aa)(Bb) x (Aa)(Bb)  This will now look like this 

16.  Mendel’s Laws: Independent assortment- allele pairs separate independently during the formation of gametes. Traits are transmitted to the offspring independently of one another Segregation- when sex cells are made, the 2 factors separate… 1 per gamete  Discoveries: factors located on our chromosomes, through gametes during fertilization, now known as alleles (different forms of the same gene)

17.  Fertilization – fusing of sperm & egg  Zygote – fertilized egg (diploid) which develops into an embryo  Meiosis – type of cell division that produces egg & sperm; occurs in ovaries & testes  Homologous Chromosomes- Carry same type of genes (though not necessarily the same version of that gene)  Draw a dihybrid punnett square: 5 across, 5 down: making 25 squares… do not take up your whole page! Use your lines on the sheet!!

18.  Mendel’s Laws: Independent assortment- allele pairs separate independently during the formation of gametes. Traits are transmitted to the offspring independently of one another Segregation- when sex cells are made, the 2 factors separate… 1 per gamete  Discoveries: factors located on our chromosomes, through gametes during fertilization, now known as alleles (different forms of the same gene)  Why can’t we use mitosis to make gametes?  Where are alleles located?  How do alleles get passed down?

19.  Fertilization – fusing of sperm & egg  Zygote – fertilized egg (diploid) which develops into an embryo  Meiosis – type of cell division that produces egg & sperm; occurs in ovaries & testes

20. Meiosis is process to split chromosome # in half Result: 4 cells each with 1 of each type of chromosome Meiosis I – halves the chromosome # Meiosis II – reduces amount of DNA by half

21.  Meiosis starts out with 1 cell that is DIPLOID (2n), (has both sets of chromosomes), and ends with 4 cells that are HAPLOID (n), (have only 1 set of chromosomes).

22. Homologous chromosomes – Carry same type of genes (though not necessarily the same version of that gene) – Ex: chromosome pair #1…both have gene for eye color in same spot…one codes for blue, other for brown

23. Synapsis Homologous chromosomes pair up (prophase I) WRITE THIS DEFINITION DOWN!! KEY TERM: Draw each in their circle!

24. Tetrad Group of 4 chromatids together during synapsis WRITE THIS DEFINITION DOWN!! KEY TERM:

25. Chiasma (chiasmata) Crossing of non-sister chromatids (see crossing over) WRITE THIS DEFINITION DOWN!! KEY TERM:

26. Metaphase I: tetrads line up Anaphase I: homologous chromosomes separate

27. Works just like mitosis Draw each in their circle!

28. MITOSIS MEIOSIS  cell division that produces 2 genetically identical diploid daughter cells ex. Somatic or body cells  This type of cell division produces identical daughter cells which leads to the development of tissues and organs  cell division that produces 4 genetically different haploid daughter cells ex. Gametes or sex cells  This type of cell division produces gametes which are all different and unique.

30. The positioning of tetrads in metaphase determines variability of resulting gametes

31.  If diploid # is 4 chromosomes 2 x 2 = 4 possible gametes  If diploid # is 6 chromosomes 2 x 2 x 2 = 8 possible gametes  If diploid # is 46 chromosomes (like us!) 2 x 2 x 2 x …x 2 = 8 million possible gametes And possibility after fertilization… 8 million x 8 million = 64 trillion possible individuals

33. Crossing over during meiosis I, nonsister chromatids of homologous chromosomes switch places Results in even more genetic variability

34.  Page 111 comparing mitosis and meiosis Work on this as individual work!! No cell phones, no talking!

35.  Law of Independent Assortment: this law simply put means that for a certain trait, the gamete can have either allele that is present in the mother/father. So during meiosis, the 2 alleles will randomly move to opposite poles and 1 of those gametes produced will be fertilized

36.  Law of Segregation: Mendel's Law of Segregation says that the two factors that govern a trait separate from each other and go into different gametes. In meiosis I the homologous chromosomes pair up and separate from each other - just like Mendel said, even though he didn't know about meiosis.

37.  4 people per lab table  Draw what each phase looks like on the paper  Write down what happens in each phase  Write the genetic material name (i.e. chromatin, chromosome, tetrad, sister chromatids)

38.  Page 112 Front page only Label each phase, and put the correct number of order each phase goes in Label every structure within each phase Write down the definitions of the new terms under the correct phase they belong to:  Tetrad  Synapsis & Chiasma (Crossing over)  Homologous pairs  Haploid cells Write a brief statement of what is going on in each phase under the phases

39.  Purebred- Homozygous dominant or recessive  Hybrid- heterozygous traits  Dominant- Capital letter-covers recessive trait  Recessive- lower case letter- gets covered, unless homozygous  Genotype- the letters used to represent the alleles  Phenotype- physical appearance

40.  Parent genotypes listed on edges  Fill in spaces…big letter listed first  List genotype (G) and phenotype (P) including fractions, percent’s, or ratios G: 4/4 Aa P: 4/4 red

41. Use information to make a punnett square under basics Include the genotype and phenotype ratios and what they mean

42. (T=tall, t=short, P=purple, p=white) TtPp x TtPp

43. TPTptPtp TP Tp tP tp (T=tall, t=short, P=purple, p=white)

44. TPTptPtp TPTTPPTTPpTtPPTtPp TpTTPpTTppTtPpTtpp tPTtPPTtPpttPPttPp tpTtPpTtppttPpttpp (T=tall, t=short, P=purple, p=white) How many different phenotypes is that?

45. TPTptPtp TPTTPPTTPpTtPPTtPp TpTTPpTTppTtPpTtpp tPTtPPTtPpttPPttPp tpTtPpTtppttPpttpp (T=tall, t=short, P=purple, p=white) P: 9/16 tall, purple3/16 short, purple 3/16 tall, white1/16 short, white

46.  1 st – Work on page 114 (individual work) Raise hand when finished to get your grade  2 nd – Bikini Bottoms 1 (pg119), you can work individually or in groups Raise hand when finished to get your grade

47. To determine genotype of a dominant phenotype organism

48.  What happens if you test 2 traits at the same time? (dihybrid cross)  What if you cross purebred yellow-round with purebred green-wrinkled? Will traits “stick” to each other? Will traits “split up” from each other?

49. Alleles are segregated (and inherited) separately

50.  Law of Independent Assortment Alleles for different traits are inherited independently or separately from each other. This occurs in Metaphase I…

51.  Law of Segregation Every individual has two alleles of each gene and when gametes are produced, each gamete receives one of these allele.  Happens during Anaphase I the homologous chromosomes separate (each chromatid has one allele per gene)

52.  Mendel’s laws still apply, but many traits due to more complicated relationships between alleles

53.  A single dominant allele inherited from one parent is all that is needed for a person to show the dominant trait.  Ex: -Earlobes attached is recessive trait - Flower color in peas

54.  Cross a person who is heterozygous for dimples and a person who is recessive for no dimples  Use the letter D & d for your dominant and recessive traits  Write down how many will have and will not have the trait

55.  Dominant partially covers recessive; heterozygotes will have an in-between phenotype Ex: curly-wavy-straight hair  Sample: G: 4/4 Hh P: 4/4 wavy

56.  Cross a person who has straight hair (hh) with a person who has curly hair (HH)  Write down the genotypes and phenotypes

57.  Both alleles dominant… both expressed (no blending in hetero’s) Ex: Human blood grps Sickle Cell Sample Problem Type AB – I A I B

58. Cross a Sickle Cell Anemia (AA) with a person who is normal (NN) Cross a heterozygous and a normal  Sample #1: G: 4/4 NA P: 4/4 s-c trait  Sample #2: G: 2/4 NN, 2/4 NA P: 2/4 normal, 2/4 s-c

59. Some traits have more than 2 possible alleles Ex: Human blood has A, B, and O Which other pattern does this reflect? codominance

60.  Practice doing your punnett squares at the bottom of 115, under Codominance and Multiple alleles  Blood types: O= ii A= IA B=IB

61.  Ranges from complete dominance to incomplete dominance to codominance  Reflects expression of alleles, NOT one allele “covering up” another  Does not reflect prevalence in population Recessive allele may be more common

62. If a black bunny (a dominant trait) is mated with a white bunny. The baby bunny is gray. What type of inheritance pattern does this express? Prove this with using a Punnett Square.

63.  For Question 1, T=tall, t=short  1. Cross a plant that is homozygous tall with a plant that is homozygous short.  What are the Phenotypes?  What are the Genotypes?

64. In humans, sex-linked genes are the ones on the X chromosome Fathers pass these on to their daughters only and mothers pass these on to both sons & daughters Males more likely to have recessive sex-linked traits Sex-linkage – Sample Problem XX - femaleXY - male

65.  Ex: male-pattern baldness; hemophilia; color-blindness

66. Due to more than one gene controlling a trait Has an “additive effect” Ex: human eye color, skin color, hair color, height

67. Ranges from complete dominance to incomplete dominance to codominance Reflects expression of alleles, NOT one allele “covering up” another Does not reflect prevalence in population – Recessive allele may be more common

68.  Phenotype depends on environment & genes  Ex: nutrition, physical activity, education,etc  Norm of reaction = range of phenotype governed by a gene Some traits have no range (blood type) Some traits have large range (esp. polygenic) Ex: Flower color differs based on pH of soil

69.  Not easy to study Generations too long Not enough offspring Cannot selectively breed  Must find alternative methods to figure out human inheritance patterns

70. Traces traits through a family Used to determine genotypes & phenotypes Used to predict probability of certain traits in future offspring

71. Purple = has disease Phenylketonuria (PKU) Is this trait due to a dominant or recessive gene? What are the genotypes for each individual?

72. Cystic fibrosis (recessive) – 1/2500 whites of European descent – 4% of whites are carriers (heterozygous) – Cl- transport is abnormal…thick mucus

73.  Phenylketonuria(PKU) (autosomal recessive) rare condition in which a baby is born w/o the ability to properly break down amino acid called phenylalanine. products containing aspartame should be avoided Phenylalanine plays a role in the body's production of melanin, the pigment responsible for skin & hair color. Therefore, infants with the condition often have lighter skin, hair, and eyes

74.  Tay-Sachs Disease (recessive) 1/3600 of Ashkenazic (European) Jews Dysfunctional enzyme that does not break down brain lipids Seizures, blindness, motor & mental degeneration

75.  Duchenne’s Muscular Dystrophy (sex-linked recessive) Muscles atrophy Gene carried on X chromosome

76.  Recessives should be rare so chance that 2 people will have exact same recessives are low  Chances increase if the 2 people are related  Lethal recessive traits much more common than lethal dominant traits…

77.  Sickle-Cell Disease (codominance) 1/400 African Americans Substitution of 1 amino acid in hemoglobin Abnormal cell shape = less oxygen = many other symptoms (pleitropic) Heterozygotes may/may not have symptoms  Codominance – both hemoglobins made  Increases resistance to malaria

78.  Hemophilia X-Linked recessive pattern (males are more affected, females carriers) 1/5000 males inherited bleeding disorder Blood doesn’t clot properly, may cause spontaneous bleeding, excessive bruising, bleed excessively during teething time, swollen bruised joints, frequent falling

79.  Recessives should be rare so chance that 2 people will have exact same recessives are low  Chances increase if the 2 people are related  Lethal recessive traits much more common than lethal dominant traits…

80.  Sickle-Cell Disease

81.  Achondroplasia Type of dwarfism 1/10,000 people  Huntington’s disease Degenerative disease of nervous system starts ~35-45 yrs of age (after reproductive age)

82.  Heart disease  Diabetes  Cancer  Alcoholism  Schizophrenia  Manic-depression

84. Male but often sterile; often with feminine characteristics

85. Male; perhaps taller than normal

86.  XXX female; nondistinguishable from XX  X0 Turner’s syndrome Female; typically sterile  0Y Not viable; would not be born

87.  For Question 1, R=red, r=white  1. A) If a pure-bred red is crossed with a pure-bred white, what will the offspring be?  B) Which inheritance pattern is this?  For Questions 2, R=red, r=white  2. This plant shows incomplete dominance… If a pure-bred red is crossed with a pure-bred white, what will the offspring be?  For Question 3, R=red, W=white  3. A) If a pure-bred red is crossed with a pure-bred white, what will the offspring be?  B) Which inheritance pattern is this?

88.  4. What is the name for this type of picture?  5. What gender is this person?  6. What defect does this person have?

89. Purple = has disease White = does not have disease 7. Is this trait due to a dominant or recessive gene? 8. What is the likeliest genotype for Daniel?

90.  9. Why can’t mitosis be used to make new sperm or egg cells?  10. In which phase of meiosis do tetrads form?  11. What is a tetrad?  12. What does Mendel’s law of independent assortment state?  13. What does Mendel’s law of segregation state?