Structure and Composition

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• Structure and Composition

DNA is sometimes called "the blueprint of life"
because it contains the code, or instructions for
building and organizing and ensuring that
organism functions correctly.
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DeoxyriboNucleic Acid

• DNA is composed of subunits called nucleotides,
  strung together in a long chain
• Each nucleotide consists of a phosphate, a sugar
  (deoxyribose), and a base

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Bases

• Bases come in two types pyrimidines
• (cytosine and thymine)
• and purines
• (guanine and adenine)

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• The sugar and phosphates make up the "backbone"
  of the DNA molecule.

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• The shape of the DNA molecule is a
  double-stranded helix (like a twisted ladder).
• The sides of the ladder are composed of
  alternating sugars (deoxyribose) and phosphates.
• The rungs of the ladder are composed of
  nucleotides.

James Watson Francis Crick
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Base Pair Rule

• Nucleotides pair in a specific way - called the
  Base-Pair Rule

• Adenine always pairs
• with Thymine (A-T)

• Guanine always pairs
• with Cytosine (C-G)

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Base Pair Rule
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• Here are some bases of DNA
• A -A-T-G-T-A-T-A-C-A-A-G-G-C-A-T
• Now match them with their complementary bases.

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RNA

• RNA is like DNA
• It stands for Ribonucleic Acid
• Its used to make proteins, whereas DNA contains
  the information of life

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What are some differences?
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What are some Differences?
DNA RNA
Double stranded Single Stranded
Sugar is deoxyribose Sugar is ribose
Uses the base Thymine (T) Instead of Thymine, it uses Uracil (U)