DNA

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DNA

• 9/24/2014

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• Function Of DNA
• Carries genetic code
• All cells have code
• DNA has same structure and function in all living
  things
• Human DNA can be read by oak tree
• DNA from cats is the same as human

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• DNA Structure
• Discovered by Watson and Crick in 1953
• 3 parts to DNA
• Deoxyribose sugar 5-C
• Phosphate PO4
• Nitrogen Bases
• Adenine A
• Guanine G
• Cytosine C
• Thymine T

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• Components are arranged in nucleotides
• 1 nucleotide Sugar phosphate 1 nitrogen
  base
• Nucleotides are arranged into a double helix
• Twisted Ladder
• Each upright of ladder is composed of a sugar
  phosphate backbone

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1. Nitrogen bases are attached to sugars

1. Ladder has 2 sides

• N-basses pair with other N-bases
• A will only pair with TT will only pair
  with AG will only pair with CC will
  only pair with G

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• DNA replication
• Happens just prior to mitosis during interphase
• Exact copy of DNA must be made
• DNA double helix unwinds
• Helix unzips (inner base pairs are exposed)
• New nucleotides attach to exposed base pairs
• A only pairs with T
• G only pairs with C
• 2 identical strands are produced
• When cell divides each daughter cell gets one

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PLEASE UNZIP AND DUPLICATE THE FOLLOWING STRAND
ATT ACG CTT AGG ACC TTC CCT TTG TCATAA TGC
GAA TCC TGG AAG GGA AAC AGT
ATT ACG CTT AGG ACC TTC CCT TTG TCATAA TGC
GAA TCC TGG AAG GGA AAC AGTATT ACG CTT AGG ACC
TTC CCT TTG TCATAA TGC GAA TCC TGG AAG GGA AAC
AGT