1. Wake-up
Explain the difference between photosynthesis and cell respiration in terms of carbon dioxide.
What would happen if there were no nitrogen-fixing bacteria?

2. EOC Review #4: Genetics, Meiosis, and Biotechnology

3. Meiosis

4. A sequence in DNA that codes (has the directions) for a trait.
What is a Gene?
A sequence in DNA that codes (has the directions) for a trait.

5. What is a Homologous Pair?
A pair of chromosomes with similar genes; one chromosome is from your mom and the other from your dad

6. Diploid? Formula: 2n n = the number of chromosomes
2 = two chromosomes; homologous pairs are present
-Normal number of chromosomes in organisms body cells

7. Haploid? Formula: n n = the number of chromosomes
-Single set of unpaired chromosomes (no homologous pairs) found in gametes.

8. Reproductive cell; Sex cell Males have sperm and females have eggs
What is a Gamete?
Reproductive cell; Sex cell
Males have sperm and females have eggs

9. Brief summary of Meiosis
Process in which gametes (sex cells) are made
Need to split apart the homologous pairs; reduce # of chromosomes by 1/2

10. DNA is Replicated
Homologous Pairs

11. Homologous Pairs are separated Sister Chromatids are separated
Process: Meiosis
Homologous Pairs
Meiosis I
Homologous Pairs are separated
Meiosis II
Sister Chromatids are separated

12. Process: Fertilization Combination of the egg an sperm
Zygote
Homologous Pairs

13. Meiosis produces four gametes (sex cells) with HALF the number of chromosomes of the original cell

14. If an organism has 50 chromosomes and it undergoes meiosis, how many chromosomes will be present in the new cells?

15. Exchange of parts between two paired chromosomes
Crossing Over
Exchange of parts between two paired chromosomes

16. Meiosis and Crossing Over

17. Law of Independent Assortment
Homologous chromosomes will separate independently of each other during meiosis

18. What is the Benefit of Sexual Reproduction/Meiosis?
Increases Genetic Variation

19. Mendelian Genetics

20. DOMINANT allele: Expressed trait; Capital letter, Always first

21. Recessive Allele
recessive allele: Only expressed if paired with another recessive; Lowercase letter

22. What is genotype?
Combination of alleles; allele letters that code for a trait; GENETIC makeup of gene

23. a. Homozygous Dominant: Two dominant alleles
Types of Genotypes
a. Homozygous Dominant: Two dominant alleles BB

24. b. Homozygous Recessive: Two recessive alleles
Types of Genotypes
b. Homozygous Recessive: Two recessive alleles bb

25. c. Heterozygous: One dominant and one recessive allele
Types of Genotypes
c. Heterozygous: One dominant and one recessive allele Bb

26. What is phenotype?
Physical expression of trait; observable characteristic; physical appearance

27. Monohybrid Crosses
Christopherson

28. Tool used to predict the genotypes and phenotypes of offspring
Punnett Square
Tool used to predict the genotypes and phenotypes of offspring

29. What is Monohybrid Cross?
Punnett square using
only one trait.

30. If purple is dominant and white is recessive, cross a purebred (homozygous dominant) purple flower with a white flower. X PP pp

31. PP x pp p p P Pp Pp P Pp Pp

32. Example #1
A male that is heterozygous for purple hair is crossed with a orange haired woman. Orange is recessive. What chance to they have in producing a purple haired child? Orange haired child?

33. Example #3
A couple is heterozygous for the gene for big nose. They are about to have a child and hope that it has a small nose. Do they have a chance? How much of a chance? B = Big nose and b = small nose

34. Special Crosses: Incomplete Dominance and Codominance

35. What is Incomplete Dominance?
Blending of the dominant and recessive alleles in heterozygous
3rd phenotype

36. Plant: Snapdragons
White: r or R` or W
Red: R

37. Pink: Rr or RR` or RW

38. What is Codominance?
Both dominant and recessive alleles are expressed in heterozygous
3rd phenotype

39. Chickens: Feather Color
Black: B
White: b

40. Black and White: Bb

41. In snapdragons, red flowers are dominant over white flowers
In snapdragons, red flowers are dominant over white flowers. The heterozygous genotype has pink flowers. Cross a homozygous red-flowered plant with a pink flowered plant. What are the chances of producing white flowers? (R = red and r = white)

42. In certain cattle, hair color can be red (homozygous RR), white (homozygous rr), or roan (a mixture of red and white hairs, heterozygous Rr). When two roan cattle mate, what genotypes and phenotypes of offspring could be obtained?

43. Multiple Alleles and Sex-linkage

44. What are Multiple Alleles?
Three or more alleles for a particular gene

45. Example: Blood Types

46. Different Blood Types in Humans
Blood Type A
IAIA
IAi

47. Different Blood Types in Humans
Blood Type B
IBIB
IBi

48. Different Blood Types in Humans
Blood Type AB
IAIB

49. Different Blood Types in Humans
Blood Type O ii

50. A man with heterozygous A blood marries a woman that is heterozygous B blood. What blood types will their kids have?

51. What are Sex-linked Traits?
Alleles that are attached to the sex chromosomes

52. Tricky thing about the Y chromosome
The Y chromosome does not hold any alleles

53. A woman who has hemophilia marries a normal male
A woman who has hemophilia marries a normal male. They are worried about their children having hemophilia. Should they worry? Explain.

54. If a man with normal color vision marries a woman who is a carrier for colorblindness, what is the probability of their having a color-blind son? A color-blind daughter?

55. Karyotypes
Christopherson

56. There are _________ chromosomes in a typical human body cell.

57. There are _________ homologous pairs within these cells.

58. What are Sex Chromosomes?
Chromosomes that determine the sex of an organism

59. Typical Female Sex Chromosomes

60. Typical Male Sex Chromosomes

61. Autosomes: Any chromosome that’s not a sex chromosome
22 pairs of Autosomes

62. What is a Karyotype?
Number and appearance of chromosome set

63. Understanding a Karyotype
Homologous pairs
Autosomes
Sex Chromosomes

64. Failure of the chromosomes to separate properly during meiosis
Nondisjunction
Failure of the chromosomes to separate properly during meiosis

65. 1 instead of 2 chromosomes
Monosomy
Gamete
Gamete
Mono – One
Missing a chromosome
1 instead of 2 chromosomes
Zygote

66. Turners Syndrome
XO-Single X chromosome

67. Having an extra chromosome
Trisomy
Gamete
Gamete
Tri – Three
Having an extra chromosome
3 instead of 2 chromosomes
Zygote

68. There is an extra 21st chromosome
Down Syndrome
Aka: Trisomy 21
There is an extra 21st chromosome

69. Human Genetic Disorders and Pedigrees
Christopherson

70. Diagram showing a family tree and patterns of inheritance.
What is a Pedigree???
Diagram showing a family tree and patterns of inheritance.

72. Recessive Trait or Disorder
Traits or disorders caused by 2 recessive alleles

73. Cystic Fibrosis
Disease that causes the body to produce unusually thick, sticky mucus that:
Clogs the lungs and leads to lung infections
Obstructs the pancreas
Stops natural enzymes from helping the body break down and absorb food

75. Types of Pedigrees: Recessive
Present/Affected Genotypes: bb
Absent/Unaffected Genotypes: BB or Bb
HINT: Recessive Disorders skip
generations

76. Generation I-III was skipped

77. Sex-Linked Trait/Disorder
Traits/disorders linked to sex chromosomes

78. Inability to see colors in the normal way
Color Blindness
Inability to see colors in the normal way

79. Inability of the blood to clot properly
Hemophilia
Inability of the blood to clot properly

80. Types of Pedigrees: Sex-linked
Present/Affected Genotypes:
XbXb or XbY
Absent/Unaffected Genotypes:
XBXB or XBXb and XBY
HINT: Mainly males are affected

81. Notice the number of males with the trait.

82. Dominant Trait or Disorder
Traits or disorders caused by a dominant allele
Affected individuals are homozygous dominant or heterozygous

83. Huntington’s Disease
Causes the break down of brain cells, (neurons) in certain areas of the brain.
Causes uncontrolled movements, loss of intellectual faculties, and emotional disturbance.

84. Types of Pedigrees: Dominant
Affected Genotypes: BB or Bb
Unaffected Genotypes: bb

85. What type of inheritance?

86. What type of inheritance?

87. What type of inheritance?

89. Genomes and Genetic Engineering
Christopherson

90. The complete set of genetic material of an organism
Genome (Video - 0:28-2:29)
The complete set of genetic material of an organism

91. Human Genome Project (24:42-
The sequence of the 3 billion base pairs (A,T,G,C) in human DNA was discovered.
This means that the sequence of the genes within our DNA is known

93. Benefits of the Human Genome Project
Improve diagnosis of diseases and help with early detection of genetic disorders

94. Gene Therapy -Swapping an abnormal gene for a normal one -Repairing an abnormal gene

95. What is Genetic Engineering?
Technology used to change the DNA of organisms to create a new useful result

96. How is Genetic Engineering possible?

97. 1. Isolate Gene
Specific “gene of interest” can be “cut” out of DNA using restriction enzymes

98. Enzyme produced by bacteria; cut DNA at specific base sequences.
Restriction Enzymes
Enzyme produced by bacteria; cut DNA at specific base sequences.

99. 2. Place the Gene of Interest into Vector
Vector = Vehicle that “carries gene of interest”;
Bacteria is the most common.

100. 2. Place the Gene of Interest into Vector
a. Cut the plasmid with same restriction enzymes used on gene of interest

101. 2. Place the Gene of Interest into Vector
b. DNA Ligase attaches the gene of interest to the cut plasmid

102. 2. Place the Gene of Interest into Vector
c. Form Recombinant DNA.
A gene from one organism is put into the genome of a different organism.

103. 2. Place the Gene of Interest into Vector
d. Recombinant DNA is placed back into bacteria cell through process called TRANSFORMATION

104. How is genetic engineering possible?
Transformation: When a cell takes up and expresses a new piece of genetic material—DNA— in order to change the organism’s traits
DNA
Protein
Trait
RNA

105. 3. Make copies of new cell

106. Transgenic Organism
An organism (animals, plants, and bacteria) that has been genetically altered.

107. Example #1: Diabetes and Insulin (Medical)

108. Insulin (protein) helps glucose move from our bloodstream to our cells
What is Insulin?
Insulin (protein) helps glucose move from our bloodstream to our cells
Glucose is from food that was consumed

109. Type 1 Diabetes: The Pancreas does not produce insulin

110. Diabetics need to take Insulin shots
How does someone with Type 1 Diabetes get insulin?
Diabetics need to test their blood sugar
Diabetics need to take Insulin shots

111. History of Insulin Production (finish)
Gene that makes insulin in humans was inserted into E.coli (Bacteria) which produced synthetic human insulin

114. Gel Electrophoresis
Christopherson

115. What is Gel Electrophoresis?
Process used to separate fragments of DNA using a charge

116. 1st Step in Electrophoresis
Prepare the gel
Need agarose, mold, and comb

117. 2nd Step in Electrophoresis
Prepare the box
Need electrophoresis chamber and buffer

118. 3rd Step in Electrophoresis
Load DNA into the wells of the gel using a micropipette
DNA
Well

119. 4th Step in Electrophoresis
Run electricity to separate DNA
fragments

120. 5th Step in Electrophoresis
Stain the gel to see the DNA fragments
Analyze results

121. + What is the Result? Larger Fragments Well DNA Fragment ___
Shorter Fragments

122. EXAMPLE I: WHO IS THE CRIMINAL?