DNA

1
Chapter 12

• DNA

2
Do now

• What are the building blocks of
• Carbohydrate
• Proteins
• Lipids
• NUCLEIC ACIDS

3
Do now

• What are the building blocks of
• Carbohydrate Monosaccharides (glucose)
• Proteins Amino Acids
• Lipids Glycerol 3 Fatty Acids
• NUCLEIC ACIDS Nucleotides

4
Remember genes on chromosomes are inside the
nucleus.
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Section Outline

• 121 DNA
• A. Griffith and Transformation
• 1. Griffiths Experiments
• 2. Transformation
• B. Avery and DNA
• C. The Hershey-Chase Experiment
• 1. Bacteriophages
• 2. Radioactive Markers
• D. The Components and Structure of DNA
• 1. Chargaffs Rules
• 2. X-Ray Evidence
• 3. The Double Helix

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I. Major DNA Experiment

• Griffiths Experiment
• Avery
• Hershey and Chase
• Wilkins vs. Franklin
• Watson Crick
• Chargaff

7
Write one sentence describing what each of these
scientists contributed to the discovery of DNA
Avery
Griffiths Experiment
Hershey and Chase
DNA
Franklin

• Watson Crick

Chargaff
8
Frederick Griffiths Experiment

• 1928, Tried to find a vaccine against pneumonia.
• Caused by a pneumococcus bacteria
• Two types of bacteria
• Type S or smooth covered capsule,
• causes pneumonia
• Type R or rough covered capsule
• Does not cause pneumonia

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Video 1
Video 1
Griffiths Experiment

• Click the image to play the video segment.

10
 Griffiths Experiment
Section 12-1
Heat-killed, disease-causing bacteria (smooth
colonies)
Harmless bacteria (rough colonies)
Control(no growth)
Harmless bacteria (rough colonies)
Heat-killed, disease-causing bacteria (smooth
colonies)
Disease-causing bacteria (smooth colonies)
Dies of pneumonia
Dies of pneumonia
Lives
Lives
Live, disease-causingbacteria (smooth colonies)
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First Step
Type-S bacteria
Type-R bacteria
Heated Type-S bacteria
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Type-S bacteria
Type-R bacteria
Heated Type-S bacteria
Second Step
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Third Step
Type-S bacteria
Type-R bacteria
Heated Type-S bacteria
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Fourth Step
Type-S bacteria
Type-R bacteria
Heated Type-S bacteria
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Fred Griffith's Experiments in Bacterial
Transformation1928

• Conclusion
• Somehow the heated-killed bacteria had passed
  their disease-causing ability to the harmless
  strain.

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Avery and DNA

• Physically and chemically treated
• (broke down) the DNA
• And other scientists discovered that the nucleic
  acid DNA stores and transmits the genetic
  information from one generation of an organism to
  the next

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So then what is a Bacterial Transformation?

• To introduce a foreign plasmid (ring of DNA) into
  a bacteria and to use that bacteria to amplify
  the plasmid in order to make large quantities of
  it.
• In English, the plasmid takes control over the
  bacteria changing the purpose/function of that
  bacteria

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Hershey and Chase Blender Experiment

• 1952
• Worked with Bacteriophage
• Used Radioactive Sulfur to tag protein coat.
• Used Radioactive Phosphorus to tag genetic
  elements (DNA).
• Use blender
• Conclusion The active component of the
  bacteriophage that transmits the infective
  characteristic is the DNA. There is a clear
  correlation between DNA and genetic information.

19
 Hershey-Chase Experiment
Section 12-1
Bacteriophage with phosphorus-32 in DNA
Phage infectsbacterium
Radioactivity inside bacterium
Bacteriophage with sulfur-35 in protein coat
Phage infectsbacterium
No radioactivity inside bacterium
20
 Hershey-Chase Experiment
Section 12-1
Bacteriophage with phosphorus-32 in DNA
Phage infectsbacterium
Radioactivity inside bacterium
Bacteriophage with sulfur-35 in protein coat
Phage infectsbacterium
No radioactivity inside bacterium
21
Figure 124 Hershey-Chase Experiment
Section 12-1
Bacteriophage with phosphorus-32 in DNA
Phage infectsbacterium
Radioactivity inside bacterium
Bacteriophage with sulfur-35 in protein coat
Phage infectsbacterium
No radioactivity inside bacterium
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Hershey Chase Experiment
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DNA Facts

1. It is Transmittable
2. MADE OF NUCLEOTIDES
3. A very large molecule consisting of thousands of
   smaller, repeating units known as nucleotides.
   (polymer)
4. DNA is found in the nucleus of the cell
5. In recent years, biochemists have found that the
   DNA of chromosomes is the genetic material that
   is passed form generation to generation
6. Genes- are sections of DNA molecules

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DNA Nucleotide
25
DNA Nucleotide
Phosphate group
Nitrogen base
deoxyribose
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DNA Nucleotide

• 1. The Basic building block of DNA and RNA
• 2. 5 types all named because pf their nitrogen
  base.
• adenine, thymine, guanine, cytosine Uracil
• 3. A DNA nucleotide is composed of three parts
• 1. A phosphate group
• 2. A deoxyribose (5-carbon sugar)
  molecule
• 3. A nitrogenous base of either
• adenine, thymine, guanine, cytosine
  Uracil

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Four DNA Nucleotides
RNA Only
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DNA Nucleotides
Purines
Pyrimidines
Adenine
Guanine
Cytosine
Thymine
Phosphate group
Deoxyribose
29
Structure of DNA
Nucleotide
Hydrogen bonds
Sugar-phosphate backbone
Key Adenine (A) Thymine (T) Cytosine (C) Guanine
(G)
30
The DNA Soap Opera by Watson, Crick, Wilkins
and Franklyn
1962 Nobel Prize Winners
1952 Kings College X-ray crystallography Died
1958
31
Watson-Crick Model

• Watson and Crick developed a model of the DNA
  molecule
• In this model, the DNA molecule consists of two
  complimentary chains of nucleotides in a ladder
  type organization
• Won the 1962 noble prize in science for their
  discovery the double helix

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Percentage of Bases in Four Organisms

• What does the data tell you???

Source of DNA A T G C
Streptococcus 29.8 31.6 20.5 18.0 Yeast 31.3 32.9
18.7 17.1 Herring 27.8 27.5 22.2 22.6 Human 30.9 2
9.4 19.9 19.8
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Chargaffs Rule

• He observed that there was a distinct ration
  between which nitrogen bases ?

BASE PAIRING AT CG
34
Do Now Can you figure out the order of the
nitrogen bases?
35
Can you figure out the order of the nitrogen
bases?
36
Double-helix Structure of DNA

• Each step of the ladder consists of nitrogenous
  bases bonded together by weak hydrogen bonds
• The two chains of the DNA molecule are twisted to
  form a spiral, or double-helix

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Watson-Crick Model

• The four nitrogenous bases of the DNA molecule
  bond together in only one way
• adenine (A)
• thymine (T)
• cytosine (C)
• guanine (G)

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DNA - A More Detailed Description
39
A Perfect Copy

• When a cell divides, each daughter cell receives
  a complete set of chromosomes.
• This means that each new cell has a complete set
  of the DNA code. Before a cell can divide, the
  DNA must be copied so that there are two sets
  ready to be distributed to the new cells.

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Interest Grabber continued
1. On a sheet of paper, draw a curving or
zig-zagging line that divides the paper into two
halves. Vary the bends in the line as you draw
it. Without tracing, copy the line on a second
sheet of paper. 2. Hold the papers side by side,
and compare the lines. Do they look the
same? 3. Now, stack the papers, one on top of the
other, and hold the papers up to the light. Are
the lines the same? 4. How could you use the
original paper to draw exact copies of the line
without tracing it? 5. Why is it important that
the copies of DNA that are given to new daughter
cells be exact copies of the original?
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Section Outline

• 122 Chromosomes and DNA Replication
• A. DNA and Chromosomes
• 1. DNA Length
• 2. Chromosome Structure
• B. DNA Replication
• 1. Duplicating DNA
• 2. How Replication Occurs

42
Structure of DNA
If unwound and tied together, your strands of DNA
would stretch 5feet long and would be only 50
trillionths of an inch wide. The human genome
contains 3 billion base pairs.
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DNA Replication

• DNA replication
• Double stranded DNA unwinds/ unzips along weak H
  bonds.
• Free nucleotides within the nucleus and
  incorporated by each unwound strand.
• This forms an identical copy.
• ( replication)
• 4. New copies in black, but identical!!!!!

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DNA Replication
Copy down this sequence pg229 A- T- C- T- G- A- C
-
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Video 2
Video 2
DNA Replication

• Click the image to play the video segment.

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Chromosome Structure of Eukaryotes
Nucleosome
Chromosome
DNA double helix
Coils
Supercoils
Histones
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(No Transcript)
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Prokaryotic Chromosome Structure (plasmid)
Chromosome
E. coli bacterium
Bases on the chromosome
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 DNA Replication
Original strand
DNA polymerase
New strand
Growth
DNA polymerase
Growth
Replication fork
Replication fork
Nitrogenous bases
New strand
Original strand
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Section Outline

• 123 RNA and Protein Synthesis
• A. The Structure of RNA
• B. Types of RNA
• C. Transcription
• D. RNA Editing
• E. The Genetic Code
• F. Translation
• G. The Roles of RNA and DNA
• H. Genes and Proteins

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Do Now

• 1. What are the three types of RNA?
• 2. Why are proteins important to the human body???

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Three types of RNA

• Messenger RNA (mRNA)- bring DNA message out of
  nucleus to ribosomes in the cytoplasm.
• Transfer RNA (tRNA)- transports amino acids in
  the cytoplasm to the ribosomes.
• Ribosomal RNA (rRNA)- make identification code of
  each ribosome for specific protein manufacturing.

All of this work is for protein synthesis!!!!!!
53
Do Now Compare and Contrast DNA and RNA

• RNA
• 1.
• 2.
• 3.
• 4.
• 5.

BOTH 1. 2. 3.
DNA 1. 2. 3. 4. 5.
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Do Now Compare and Contrast DNA and RNA

• DNA
• Deoxyribose
• Thymine.
• Double stranded
• Nucleus only
• 5. Is the TEMPLATE that forms an mRNA strand

• RNA
• Ribose
• Uracil
• Single Stranded
• 4. Formed in nucleus and moves into cytoplasm
• 5. carries information from DNA in the nucleus
  to the cytoplasm and helps in the protein
  synthesis demands of a cell

BOTH Nucleic acid Genetic information made
of Nucleotides
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RNA(Ribonucleic acids)

• functions to carry information from DNA in the
  nucleus to the cytoplasm and helps in the protein
  synthesis demands of a cell.

• RNA vs. DNA
• Ribose instead of Deoxyribose
• Uracil is substituted for thymine.
• Single Stranded not double stranded

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Do Now

• 1. What are the three types of RNA?
• 2. Why are proteins important to the human body???

57
RNA(Ribonucleic acids)

• functions to carry information from DNA in the
  nucleus to the cytoplasm and helps in the protein
  synthesis demands of a cell.

• RNA vs. DNA
• Ribose instead of Deoxyribose
• Uracil is substituted for thymine.
• Single Stranded not double stranded

58
Three types of RNA

• Messenger RNA (mRNA)- bring DNA message out of
  nucleus to ribosomes in the cytoplasm.
• Transfer RNA (tRNA)- transports amino acids in
  the cytoplasm to the ribosomes.
• Ribosomal RNA (rRNA)- make identification code of
  each ribosome for specific protein manufacturing.

All of this work is for protein synthesis!!!!!!
59
Concept Map
RNA
can be
also called
which functions to
also called
also called
which functions to
which functions to
from
to
to make up
60
Genetic Code

• A genetic code contains the information for the
  sequence of amino acids in a particular protein
• This code is present in mRNA molecules and is
  three bases long. This is known as a codon
• Ex UAG - is a codon

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Messenger RNA (mRNA)

1. When portions of DNA molecules unwind and
   separate, RNA nucleotides pair with complimentary
   bases on the DNA strand. This forms a mRNA that
   is complimentary to the DNA strand
2. The sequence of nucleotides in the mRNA contain
   the genetic code
3. The genetic code for each amino acid is a
   sequence of three nucleotides forming a codon

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Messenger RNA (mRNA)

• Example Here the mRNA is complimentary to the
  DNA.
• The DNA serves as the original template.
• DNA mRNA
• T A
• A U
• C G
• (AT GC in RNA use U instead of T)

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mRNA Genetic codes
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The Genetic Code
Section 12-3
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Do Now

• Describe the two steps to polypeptide synthesis.

66
Do Now Answers

• Describe the two steps to polypeptide synthesis.
• 1. Transcription
• 2. Translation

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Replication vs. Protein synthesis
68
Animated Translation
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Protein Synthesis

• Transcription
• Uses the DNA template to make an mRNA strand
  inside the nucleus.
• mRNA strand exits the nucleus through a nuclear
  pore.

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Protein Synthesis Step 1 Transcription
Remember DNARNA A - U C - G
G - C T - A
Occurs in the __ _____
1 Is _________ . By using a ___________it
unzips by breaking the weak H bonds.
2. mRNA nucleotides bond to DNA _________ and
form an mRNA chain.
DNA Strand
TAC AAT AGC CAT
_ _ _ _ _ _ _ _ _ _ _ _
-DNA TEMPLATE -mRNA STRAND
TAC ATT AGC CAT
_ _ _ _ _ _ _ _ _ _ _ _
3. mRNA leaves nucleus
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4. mRNA enters the cytoplasm
mRNA______
5. Ribosome and rRNA line up with the first
start mRNA codon.
AUG UAA UCG GUA
_______________
6. tRNA nucleotide carrying an amino acid
7 Specific tRNA lines up with mRNA at Ribosome
8. Amino Acids bond forming a polypeptide
chain. (Protein)
Ribosome
AUG UAA UCG GUA
rRNA
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Protein Synthesis

• Translation
• 1. In the cytoplasm, the mRNA strand becomes
  associated with a ribosome and an rRNA molecule
• 2. Amino acids in the cytoplasm are picked-up
  by molecules of transfer RNA (tRNA)
• 3. Each codon on the mRNA bonds with a
  corresponding anticodon on a tRNA, which carries
  a specific amino acid
• 4. The resulting chain of amino acids is a
  polypeptide.

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Transcription
Adenine (DNA and RNA) Cystosine (DNA and
RNA) Guanine(DNA and RNA) Thymine (DNA
only) Uracil (RNA only)
RNApolymerase
DNA
RNA
74
Translation
Section 12-3
75
Translation (continued)
Section 12-3
76
Label the following structures
Do Now
77
Do Now

• Identify three ways to separate materials in a
  science lab

78
Do Now Answers

• Identify three ways to separate materials in a
  science lab
• Gel electrophoresis
• Not restriction enzymes those are used to cut DNA
• Chromatography
• UltraCentrifuge

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Section Outline

• 124 Mutations
• Gene Chromosome theory
• Gene Expression
• Heredity and the Environment
• Gene Linkage
• Gene Mutation
• Deletion, insertion
• Chromosome Mutations
• Downs syndrome,

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Gene-Chromosome Theory

• Genes exist in a linear fashion on chromosomes
• Two genes associated with a specific
  characteristic are known as alleles and are
  located on homologous chromosomes

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Gene-Chromosome Theory for a typical Teenage boy
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Do Now
83
Gene Mutations Substitution, Insertion, and
Deletion
Deletion
Substitution
Insertion
84
Gene Expression

• You have at least 2 genes for every trait.
• Genes that are on are expressed
• Genes that are off are not expressed
• Mechanisms that can switch genes on and off
  include
• Intracellular Chemicals
• Enzymes
• The Environment

85
How old are we?
23, So whats the difference?
86
Heredity and the Environment

• The development and expression of inherited
  traits can be influenced by environmental factors
  such as
• Nutrients
• Sunlight
• Temperature
• Normal white with black ears, shave the back and
  apply an ice pack the hair will grow back
  BLACK!!!

87
Gene Linkage

• Genes for different traits are located on the
  same chromosome pair, and are said to be linked
• Therefore they are usually inherited together

Red hair and freckles
88
Human Disorders associated with Sex-Linked Genes

• Hemophilia- disease in which the blood does not
  clot properly
• Colorblindness- inability to see certain colors,
  most commonly red and green
• Both of these disorders are more common in
  males than in females because a female will not
  show the disorder as long as she has one normal
  gene. Females who are heterozygous for a
  sex-linked trait are said to be carriers for that
  trait

89
(No Transcript)
90
Mutagenic Agents

• Causes mutations
• Radiation- ultraviolet light, x-rays,
  radioactive substances
• Chemicals- asbestos fibers

91
Genetic Mutations

• Changes in genetic material are called mutations
• If a mutation occurs in the sex cell, it may be
  transmitted to the offspring (sperm or egg)
• Mutations in body cells may be passed on to new
  cells of the individual due to mitosis, but will
  not be transmitted to the offspring by sexual
  reproduction, Ex cancer
• Mutations can be classified as
• chromosomal alterations or gene mutations

92
Chromosomal Mutations
Deletion
Duplication
Inversion
Translocation
93
Chromosomal Alterations

• Changes in the number of chromosomes or in the
  structure of the chromosome
• The are often visible in the phenotype of an
  organism because many genes are usually involved.
• An example
• Translocation (deletion, inversion, addition)
• Nondisjuction
• Polyploidy
• Changes in the chromosomal structure

94
Nondisjunction

• One or more pairs of homologous chromosomes fails
  to separate.
• This results in gametes with more
• (or less) than their normal haploid chromosome
  number

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Nondisjunction During meiosis
96
How does nondisjuction affect a gametes monoploid
number?

• Normal sperm or egg (n) 23,
• Nondisjuction in humans (n) 22, 24, 25, 45
• If these gametes are involved in fertilization,
  the resulting zygote may have more (or less) than
  the normal diploid chromosome number. 2n 45,
  47, 48, 68

97

• Results of Nondisjunction in humans
• 1. Downs Syndrome- extra 21 chromosome.
• This is due to the nondisjunction of chromosome
  21 in one of the parents.
• Kleinfelters Syndrome Extra X chromosome (X,X,Y)
• Turners Syndrome Missing a sex chromosome (X,0)
• 4. Triploid having 1 extra of every homologous
  pair (69) chromosomes)
• 5. Polyploidy- sometimes all 22 chromosomal
  pairs fail to separate. The resulting 2n gamete
  fuses with the normal n gamete, producing a 3n
  zygote. This is common in plants but rare in
  humans

98
Down Syndrome
99
Gene Mutations

• Involves a random change in the chemical nature
  of the genetic material (DNA)
• Some gene mutations, like albinism are obvious,
  while others are not noticeable
• (Several different genes are involved with
  pigment production, including genes on
  chromosomes 9,10, 11,13,15 and X, but it's not
  clear exactly what role each of these plays in
  the condition. In most cases there is no family
  history and the children are born to parents with
  normal pigmentation for their race.)

100
N Normal Pigmentationn Albinism recessive
101
Gene Mutations albinism
About one in every 17,000 people have Albinism.
These individuals fail to produce melanin, a
photoprotective pigment. While melanin's role in
protecting us from ultraviolet light is
understood, it also has other important functions
in the development of the retina and brain and
their interconnection of which we know much
less..
102
Muscular Dystrophy

• Muscular dystrophies are a group of more than 20
  different genetic neuro-muscular disorders, some
  more debilitating than others.
• They include Congenital Muscular Dystrophy (CMD),
  Duchenne Muscular Dystrophy (DMD), Becker
  Muscular Dystrophy (BMD), Facioscapulohumeral
  Dystrophy (FSH) and others. Most involve
  mutations in genes involved in muscle structure
  and function - in Duchenne MD for example, there
  is a single genetic fault in the production of a
  protein in muscle fibres called dystrophin.

103
Section Outline

• 125 Gene Regulation
• A. Gene Regulation An Example
• B. Eukaryotic Gene Regulation
• C. Development and Differentiation

104
Typical Gene Structure
Section 12-5
Promoter(RNA polymerase binding site)
Regulatory sites
DNA strand
Start transcription
Stop transcription
105
Video 3
Video 3
DNA Transcription

• Click the image to play the video segment.

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Video 4
Video 4
Protein Synthesis

• Click the image to play the video segment.

107
Video 5
Video 5
Duplication and Deletion

• Click the image to play the video segment.

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Video 6
Video 6
Translocation and Inversion

• Click the image to play the video segment.

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Video 7
Video 7
Point Mutations

• Click the image to play the video segment.

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Do Now
Finish this statement The only way Genetic
diseases can be inherited from _________ to
________ is through the DNA codes found in
______ ________. Two examples are _____ and
_____.
111
Do Now
Finish this statement The only way Genetic
diseases can be inherited from _________ to
________ is through the DNA codes found in
______ ________. Two examples are _____ and
_____.
Parents
Offspring
SEX CELLS
Sperm Egg
112

• Malfunctions
• And
• DNA Technologies

113
(V) Human Genetic Disorders
114
1. Phenylketonuria (PKU)

• A disorder in which the body cannot make an
  enzyme necessary for the normal conversion of
  phenylalanine
• autosomal recessive disorder, (caused by
  mutations in both alleles of the gene for
  phenylalanine hydroxylase (PAH),
• found on chromosome 12
• Results in mental retardation and organ damage

115
2. Sickle-cell Anemia

• A gene mutation that results in the production of
  abnormal hemoglobin molecules and abnormal red
  blood cells
• Most common in African Americans

116
3. Tay-Sachs

• Deterioration of the nervous system due to the
  accumulation of fatty material as a result of the
  inability to synthesize a specific enzyme
• Jewish people of Central Europe descent

117
Tay-Sachs
By about two years of age, most children
experience recurrent seizures and diminishing
mental function. The infant gradually regresses,
losing skills one by one, and is eventually
unable to crawl, turn over, sit, or reach out.
Other symptoms include increasing loss of
coordination, progressive inability to swallow
and breathing difficulties. Eventually, the child
becomes blind, mentally retarded, paralyzed, and
non-responsive to his or her environment.
118
(VI) Types of Genetic Disorder Detection
Techniques
119
1. Screening

• Chemical analysis of body fluids such as blood
  and urine
• Detection of PKU and
• Tay-Sachs

120
Replication
121
2n 46 n23
Normal somatic cell Sperm cell
122
Amniocentesis

• Fetal cells are removed and surveyed for genetic
  disorders

123
2. Karyotyping

• The preparation of an enlarged photograph of
  chromosomes

Karyotype animation http//gslc.genetics.utah.edu
/units/disorders/karyotype/karyotype.cfm
124
Normal MAle
125
Normal feMAle
126
3. Amniocentesis

• Removal of amniotic fluid for chemical and/or
  cellular analysis
• Detection of sickle-cell anemia

127
4. Remember Sex Linked Diseases????

• Hemophilia
• Colorblindness
• Duchene's Muscular Dystrophy
• Achondroplasia

128
4. Remember Sex Linked Diseases????

• Y is it easier for a male to inherit an X sex
  linked disease then a female?

129
Genghis Khan's legacy? Genes of History's
Greatest Lover?

• According to an international team of
  geneticists, about 1 in 12 men in Asia--and
  therefore 1 in 200 men worldwide--carry a form of
  the Y chromosome that originated in Mongolia
  nearly 1,000 years ago.
• Of course, this is a guess because we dont have
  Genghis Khans DNA. (1162-1227)
• His tomb remains hidden although the search is on
  to find it. Once we have his DNA, then we can
  determine if he really was as prolific as this
  data suggests.

130
Pedigree

• Is a diagram that shows the occurrence
  appearance, or PHENOTYPES of a particular genetic
  trait.

male
Marriage line
female
children
131
Pedigree of hemophilia in the Romanov family
132
Pedigree of hemophilia in the Romanov family
133
Pedigree of hemophilia in the Romanov family
134
Anastasia AKA Anna Anderson or not ???

• Anna Anderson claimed of being the Grand Duchess
  Anastasia and that as a child she had escaped her
  captors 1n 1919
• Her claims were fought over by the royals of
  Europe throughout the 20th century.
• How did they solve this problem???
• Anna Anderson was not related to the Romanovs.
  When she died, she was cremated, but samples of
  tissue were in possesion of a hospital where Ms.
  Anderson was operated on. Also found were locks
  of her hair after her husband, John Manahan
  passed away. Tests done comparing the DNA from
  Anna's tissue to the Romanov tissue found no
  match.

135
Anastasia AKA Anna Anderson or not ???

• How did they solve this problem???
• As per instructions when she died, she was
  cremated, but samples of tissue were in
  possession of a hospital where Ms. Anderson was
  operated on.
• Also found were locks of her hair after her
  husband, John Manahan passed away. Tests done
  comparing the DNA from Anna's tissue to the
  Romanov tissue found no match.
• Then who was she??????

136
Separation Techniques

• Chromatography-to make visible pigments and
  extracts
• Centrifuge-separates based on densities
• Gel Electrophoresis Separates into DNA fragments

137
Gel Electrophoresis

• is a procedure for separating a mixture of DNA
  molecules through a stationary material (gel) in
  an electrical field.

http//learn.genetics.utah.edu/units/biotech/gel/
138
Gel Electrophoresis
http//learn.genetics.utah.edu/units/biotech/gel/
139
Gel Electrophoresis
140
1 Gene to 1 Polypeptide Hypothesis

• Each gene directs the synthesis of a particular
  polypeptide (protein) chain.
• Genes control the synthesis of enzymes. SO If
  we mutate that gene it will affect the creation
  of that enzyme..

141
Genetic Engineering

• Now that we understand genes we can change the
  DNA of a cell.
• The procedure for producing altered DNA is called
  genetic engineering
• Altered DNA is called Recombinant DNA.
• Gene splicing involves the breaking of a DNA
  molecule and inserting or attaching new genes by
  means of a chemical splice.

142
Genetic Engineering

• Recombinant DNA due to Gene splicing
• Medical
• Human insulin producing bacteria
• Human Growth Hormone (HGH) producing bacteria
• Diabetic-donor corrective gene therapy
• Agriculture and Forestry
• Pest Resistant Crops (corn)
• Antibiotic Rich Corn
• HGH infused trout (live stock)
• Inc Growth rate in trees and insect repellent
  trees (logging)

143
DNA Technology

• Makes it possible to put new genes into
  organisms.
• 1. Human genes can be inserted into bacteria.
• 2. These altered bacteria become factories
  that produce human protein.
• ex Gene Splicing
• Recombinant DNA

144
VI Genetic Engineering

• Genetic Engineering- is a new technology that
  humans use to alter the genetic instructions in
  organisms.
• a) Biotechnology- The application of
  technology to biological science.
• ex removal of dinosaur DNA from a
  mosquitos last meal.
• b) Selective Breeding- A process that
  produces domestic animals and new varieties of
  plants with traits that are particularly
  desirable.

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Selective Breeding
An Example of Selective Breeding An Example of Selective Breeding An Example of Selective Breeding
                   Brahman cattleGood resistance to heat but poor beef.                    English shorthorn cattle Good beef but poor heat resistance.                    Santa Gertrudis cattle Formed by crossing Brahman and English shorthorns has good heat resistance and beef.
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Recombinant DNA

• Allows scientists to insert the insulin gene into
  bacterial plasmids.
• The bacteria that contain this gene produce
  insulin, which is used by people with diabetes.

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What is Gene Splicing?
A dessert?
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Gene SplicingTransgenic miceSlicing jellyfish
DNA in a mouse's genome!!!
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Genetic Engineering and Therapies

• Genetic engineering attempts to correct genetic
  defects, alter foods , and fight diseases.
• Gene therapy replaces defective genes with normal
  genes.
• Gene splicing using plasmids (ring shaped
  sections of bacterial DNA) can be used to create
  desirable traits.

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Plasmids

• Are small DNA fragments, are known from almost
  all bacterial cells.
• Plasmids carry between 2 and 30 genes. Some seem
  to have the ability to move in and out of the
  bacterial chromosome

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Superhero Gene Splicing
Foreign DNA
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Gene Splicing
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Gene Splicing
plasmids
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Biotechnology
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Biotechnology
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Biotechnology
Each bacterial cell can now make human insulin
Each bacterial cell has the gene for making human
insulin.
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Gene Splicing
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Gene Splicing
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Gene SplicingTransgenic miceSlicing jellyfish
DNA in a mouse's genome!!!
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Gene Splicing

• Allows a scientist to make cuts of DNA from 2
  complimentary different organisms, perhaps a frog
  cell and a bacterium.
• Pieces of DNA from one organism can now be glued,
  or spliced, into the DNA of another organism.

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Plasmids

• Are small DNA fragments, are known from almost
  all bacterial cells.
• Plasmids carry between 2 and 30 genes. Some seem
  to have the ability to move in and out of the
  bacterial chromosome

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Cloning from Adult Vertebrate Cells
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Cloning

• A clone is a group of individual organisms that
  have exactly the same genes.
• Organisms that reproduce asexually produce
  clones, since each offspring receives an exact
  copy of the genes of the parent.
• Dolly, 276 tries, 277 dolly

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Cloning
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Cloning

• Is a technique that accomplishes the same end
  result as asexual reproduction.
• It is a way of making identical genetic copies.
• Cloning is done by inserting a nucleus from a
  parent organisms cell (one that has a complete
  set of genetic information from that individual)
  into an egg cell from which the nucleus has been
  removed. The result is an egg that now contains
  not 50, but 100 of the genetic information from
  a single parent.
• If this new egg cell with all of its genes can be
  made to develop normally, the resulting offspring
  is a clone of the individual that donated the
  original cell (In mammals, the egg would be
  implanted and develop inside the body of the
  female).

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Cloning
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Population Genetics

• A population is a group of organisms of the same
  species living together in the same region
  (interbreeding).
• Population genetics is the study of changes in
  the genetic makeup of populations.
• Gene Pool The total of all the genes in a
  population at any given time.

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Population Genetics

• Gene frequencies how often (frequent) a specific
  gene shows up in a population.

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Population Genetics

• The Hardy Weinberg Law Under certain conditions
  the relative frequencies of alleles for a given
  trait in a population do not change. For this to
  be true
• The population must be large
• Individuals must not migrate into or out of the
  population.
• Mutations must not occur
• Reproduction must be completely random.