D.N.A

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D.N.A
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Tuesday 11/3/15

• Learning Target
• Describe the History of how and who discovered
  the structure of DNA.
• Learning Outcome
• Know the scientist involved and what they did in
  discovering DNA.

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D.N.A. is a Nucleic Acid

• D.N.A is capable of
• carrying genetic information to next
  generation
• directing the cell to follow its orders
• being easily copied

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DNA History

• Griffith 1928
• Grew 2 distinct strains of bacteria (rough and
  smooth), injected mice and observed which died
• Transformation one strain permanently changed
  into another

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More History

• Avery 1944
• Wanted to determine what was responsible for
  transformation
• Used enzymes to determine that DNA was the
  transforming factor.
• Hershey-Chase 1952
• Studied viruses (bacteriophages)
• Determined that genetic information was not
  protein but DNA

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Chargaff discovers the percentage of bases in
four organisms
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

• He found that there were the same percentages of
  A and T as well as G and C

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History of the Discovery of D.N.A

• 1952 Rosalind Franklin studies the DNA molecule
  using a technique called X-ray diffraction.

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History of D.N.A. Contd.

• Watson and Crick
• They used Rosalind Franklins pictures of DNA to
  figure out the structure of D.N.A.
• established the structure as a double helix -
  like a ladder that is twisted. The two sides of
  the ladder are sugar phosphate backbone and are
  held together by hydrogen bonds.

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Wednesday, 11/4/15

• Learning Target
• Know the structure of DNA
• Learning Outcome
• Be able to describe how the DNA is structured
  including nitrogen base pairs, nucleotides and
  DNA replication.

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Basic Structure of D.N.A.

• The sides of D.N.A. alternate Sugar and
  Phosphate. (sides of the ladder)
• The bases make up the middle (rungs of the
  ladder)
• A T
• C - G

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DNA Deoxyribonucleic acid

• The building blocks of DNA are nucleotides, each
  composed of
• a 5-carbon sugar called deoxyribose
• a phosphate group (PO4)
• a nitrogenous base (4 types)
• Adenine (A), thymine (T), cytosine (C), guanine
  (G)

Phosphate group
Deoxyribose (sugar)
Nucleotide!
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DNA Structure

• The two strands of nucleotides are antiparallel
• Basically, one side runs right side up and one
  side runs upside down.

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The 4 Bases

• Bases come in two types
• 1. Pyrimidines (cytosine and thymine) Have one
  ring of carbon
• 2. Purines (guanine and adenine) Have two rings
  of carbon
• 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
• Purines pair with Pyrimidines
• Adenine with Thymine
• Guanine with Cytosine

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Monday, 11/9/15

• Learning Target
• Be able to describe the process of DNA
  replication.
• Learning Outcome
• I will know the steps of DNA replication
  including DNA helicase, DNA polymerase, and base
  pairs.

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DNA Chromosome Structure
Think back When did we learn that DNA had to be
replicated?? During the cell cycle in S phase
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DNA Replication

• Replication Steps
• DNA unzips
• New nucleotides assemble
• Two new strands of identical DNA are reproduced
  each with one original stand.

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Replication Enzymes

• 2 Main enzymes involved
• 1. Helicase unzips the DNA
• 2. DNA polymerase
• It has two main functions.
• 1. Adds new bases
• 2. proofreads

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Transcription

• Transcription is the process of copying the code
  of DNA into RNA so it can go to the ribosome and
  make protein.

Transcription takes places in the
NUCLEUS A-U C-G T-A
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Transcription

• 3 STEPS
• 1. RNA polymerase (another enzyme) binds to the
  promoter region of DNA
• 2. RNA polymerase unzips the DNA and adds
  nucleotide bases
• A-U, C-G
• 3. RNA polymerase stops when it comes to a
  termination region of DNA

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Practice/Review

• So if one side of DNA has the following bases,
  what would the other side have?
• A C T G G T A C G A T A
• T G A C C A T G C T A T
• Using the original strand above, what would the
  RNA strand look like?
• U G A C C A U G C U A U

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Friday, 11/13/15

• Learning Target
• Identify how synthesized proteins have a variety
  of specific functions.
• Learning Outcome
• I will know the different functions of proteins.

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Proteins
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Proteins

• What is a protein?
• A protein is a large molecule made of smaller
  parts called amino acids. Every protein has a
  specific order of amino acids!
• 20 amino acids exist in nature
• The instructions for the order of amino acids
  comes from DNA
• Proteins are the building block for ALL living
  things!

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• What do proteins do?
• Proteins have a variety of different functions
  that include
• Structure
• Transport
• Enzymes
• Storage
• Hormonal
• Movement
• Defense

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What proteins do

• Proteins have several functions
• Structure
• Keratin protein found in hair, fur and feathers
• Transport
• Hemoglobin transports oxygen in vertebrates
• Enzymes
• Digestive enzymes break down food
• Storage
• Casein found in milk, gives protein to young
  mammals
• Hormonal
• Insulin regulates blood sugar
• Movement
• Actin and Myosin responsible for muscle movement
• Defense
• Antibodies fight of infection and disease
  (immune system)

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Protein Production

• Where is DNA located in the cell?
• Nucleus!
• Where are proteins produced?
• Ribosomes in the cytoplasm!
• How do we get the instructions from the nucleus
  to the ribosomes?
• RNA!

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Quick Quiz

1. What two individuals discovered the structure of
   DNA?
2. What are the 3 parts of the nucleotide?
3. What are the two pyrimidines?
4. What are the two purines?

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The Big Picture

• When we want to make a protein we have to
  transfer the code from DNA on to a special
  molecule called RNA!
• This is called Transcription.

So how do we get from the code from the bases to
really make us a protein?
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RNA

• RNA stands for Ribonucleic Acid.
• It is a special molecule that carries the code
  from DNA out to the ribosomes so that we can make
  the right protein.
• It is our messenger!!

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RNA

• Similarities
• Phosphate
• Sugar
• Base
• Differences
• Sugar is ribose (DNA deoxyribose)
• Single stranded (DNA double helix)
• Has uracil as a base, not thymine
• It can travel outside of the nucleus.

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3 Types of RNA
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mRNA

• messenger RNA (mRNA) serve as messengers from
  DNA to the rest of the cell

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rRNA

• Ribosomes are made up of several dozen proteins,
  as well as a form of RNA known as ribosomal RNA
  (rRNA).

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tRNA

• transfers each amino acid to the ribosome
• as specified by coded
• messages in mRNA.

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Monday, 11/16/15

• Learning Target
• Be able to describe the process of
  transcription.
• Learning Outcome
• I will know the steps of transcription.

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Tuesday, 11/20/15

• Learning Target
• Be able to describe the process of translation.
• Learning Outcome
• I will know the steps of transcription.

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Translation
Now that we have our mRNA it is time to make a
protein..we do this at the ribosome.

• Translation converting mRNA into a protein.
• To do this we use transfer RNA

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Transfer RNA

• Transfer RNA (tRNA) looks like a cross. It has
  three bases that attach at the bottom.
• We call these anti-codons.
• They attach to three bases on the mRNA which we
  call codons.
• At the top of the tRNA is an amino acid (the
  building block of proteins)!!

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Translation

• Steps 8 easy steps!!
• 1. The newly made mRNA travels to the ribosome.
• 2. The ribosome reads the mRNA code in groups of
  three, called codons. Starts at AUG
• 3. Codons match up with anticodons
• 4. Another tRNA attaches to the next codon. Its
  amino acid is attached to the previous one.

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Translation

• 5. The first tRNA falls off
• 6. The ribosome moves along the mRNA, using tRNA
  to attach amino acids.
• 7. The process ends when a stop codon is reached
  (UGA, UAA, UAG).
• 8. The amino acid chain is released it FOLDS
  into a 3-D structure called a protein.

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Amino Acid Chart

• So how do we know what amino acid is at the top
  of each transfer RNA? We use this cool chart.
  Start at the middle and work towards the outside.
  Remember amino acids go together to make
  proteins.

This chart is based on mRNA codons!!

• Practice
• 1. UCC
• Serine
• AAG
• Lysine
• UAA
• Stop

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Lets Pull everything together!

• Practice
• Given the following DNA strand, give the
  corresponding mRNA strand that it would code for.
• DNA T A C A C C T C A A T T
• mRNA A U G U G G A G U U A A
• Now, use your chart and figure out the amino acid
  chain, that this mRNA would code for.
• Methionine Tryptophan Serine STOP
• http//learn.genetics.utah.edu/content/begin/dna/t
  ranscribe/

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Monday, 12/1/14

• Learning Target
• Know the 2 types of mutations called point
  mutations and frameshift mutations.
• Learning Outcome
• I will know how to distinguish between point
  mutations and frameshift mutations.

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Mutations

• Mutations are changes in the DNA sequence that
  affect genetic information
• 1. Point Mutation
• Substitution base changed
• Original strand TAC GCA TGG
• Mutated strand TAC GTA TGG
• 2. Frameshift Mutation
• Insertion base added
• Original strand TAC GCA TGG
• Mutated strand TAT CGC ATG G
• Deletion base removed
• Original strand TAC GCA TGG
• Mutated strand TCG CAT GG

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Mutations

• Types of chromosomal Mutations (changes in whole
  chromosomes)