DNA deoxyribonucleic acid and RNAribonucleic acid

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DNA (deoxyribonucleic acid) and RNA(ribonucleic
acid)

• DNA structure and function
• REPLICATION
• TRANSCRIPTION (DNA to RNA)
• TRANSLATION (RNA to protein)
• MUTATIONS

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Structure and Function of DNA

• NUCLEOTIDES
• One of 4 nitrogen bases
• Sugar molecule (deoxyribose)
• Phosphate molecule
• DNA- chains of nucleotides (bonding pairs)
• THE DOUBLE HELIX
• FUNCTION OF DNA

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FOUR NITROGEN BASES OF DNA
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BUILDINGONESIDE OFADNAMOLECULE
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BASE PAIRINGS IN DNA
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THE OTHERHALFOF A DNAMOLECULE
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FUNCTION OF DNA

• Stores the genetic code for making proteins
• Proteins form the structures of cells and control
  all chemical processes (enzymes) within the cell.
• Carries the code to all offspring by replicating
  itself in mitosis and meiosis

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DNA REPLICATION

• Weak hydrogen bonds between base pairs are broken
  by DNA replicase enzyme
• Free nucleotides are brought in to match the
  existing base sequence of each DNA half
• New base pairs bond and the DNA is replicated
  (duplication of DNA)

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DNA REPLICATION
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DNA vs RNA

• Double strand of nucleotides
• Sugar is deoxyribose
• Nitrogen bases are thymine, adenine, guanine, and
  cytosine

• Single strand of nucleotides
• Sugar is ribose
• Nitrogen bases are uracil, adenine, guanine, and
  cytosine

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RNA DIFFERENCES

• Uracil replaces thymine as a base
• Ribose sugar replaces deoxyribose sugar
• RNA is a single strand

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TYPES OF RNA

• mRNA - messenger RNA, carries the
  protein code from DNA out to the cytoplasm.
• tRNA - transfer RNA, brings the amino
  acid to the site of protein production.
• rRNA - ribosomal RNA, makes ribosomes.
  

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RNA TRANSCRIPTION

• Gene segment that codes for specific protein is
  unzipped
• Free mRNA nucleotides align according to the code
  on the DNA strand
• mRNA releases from DNA template and moves out
  into the cytoplasm

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RNA TRANSCRIPTION
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THYMINE TO URACIL
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PROTEIN TRANSLATION andPRODUCTION

• mRNA serves as the template for protein synthesis
• mRNA attaches to the surface of a ribosome
• Every 3 base unit is called a codon
• The codon is the code for a specific tRNA
• Each tRNA has a 3 letter (base) anticodon that is
  the opposite of the mRNA

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HOW TO MAKE A PROTEIN
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tRNA and PROTEIN SYNTHESIS

• tRNA is specific for one type of amino acid
• The three letter anticodon of tRNA matches the
  three letter codon of mRNA
• The ribosome moves down the mRNA template reading
  each codon and matching it with the appropriate
  tRNA anticodon
• As the ribosome moves on to the next codon the
  amino acid from the tRNA is removed and stays
  with the ribosome

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tRNA and PROTEIN SYNTHESIS cont.

• As the next tRNA brings in another amino acid,
  the ribosome bonds it to the previous amino acid
• The type of bond formed between amino acids is
  called a peptide bond
• A strand of bonded amino acids form a protein
  (protein synthesis)

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RECHARGING tRNA WITH AN AMINO ACID
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BUILDING A PROTEIN
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3 GENES 3 DIFFERENT PROTEINS
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PROTEIN SYNTHESIS AT THE RIBOSOME
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RNA to AMINO ACID

• Find the first letter of the codon on the left
  side of the table, the amino acids that begin
  with that letter are to the right
• The second letter of the codon is on the top of
  the table, find where the first and second letter
  rows intersect
• The third letter of the codon is along the right
  side of the table, locate where the third letter
  intersects the first and second letter, this is
  the amino acid coded for by RNA

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MUTATIONS

• Point mutations
• Crossing over
• Chromosomal
• Deletions
• Insertions
• Inversions
• translocations
• Nondisjunction
• Trisomy
• monosomy

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POINT MUTATION
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CROSSING OVER
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DELETION
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INSERTION
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INVERSION
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TRANSLOCATION
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NONDISJUNCTIONTRISOMY and MONOSOMY