DNA

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DNA
The Blueprint of Life

• deoxyribonucleic acid

History Overview of DNA
Objective E1 - Identify the components of DNA,
describe how information for specifying traits is
carried in DNA, recognize that components that
make up the genetic code are common to all
organisms
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I. The History of DNA

• A. Avery, Oswald (1944)
• 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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• B. ALFRED HERSHEY MARTHA CHASE (1952)
• CONCLUDED THAT THE GENETIC MATERIAL OF THE
  BACTERIOPHAGE WAS DNA, NOT PROTEIN

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• C. Chargaff, Erwin
• discovered a relationship in the nitrogenous
  bases
• ADENINE (A) THYMINE (T) GUANINE (G)
  CYTOSINE (C)

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• D. Rosalind Franklin (1952)
• TOOK AN X-RAY OF THE DNA STRUCTURE SO THE
  PATTERNS COULD BE SEEN
• THE X-RAYS SHOW THAT DNA IS TWISTED AROUND EACH
  OTHER LIKE A HELIX AND HAS 2 STRANDS

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• E. Watson and Crick (1953)
• STUDIED THE STRUCTURE OF DNA BY BUILDING A 3-D
  MODEL OF THE MOLECULE AFTER USING CLUES FROM
  FRANKLINS X-RAY OF DNA.

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• proposed that DNA is made up of 2 chains of
  nucleotides held together by nitrogenous bases
  that the 2 strands are twisted together in a
  shape called a double helix.

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II. Overview of DNA
Nucleus
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• Chromosomes are made up of super coiled DNA

Base pairs
Histone Proteins
DNA (double helix)
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Structure of DNA

• Made up of nucleotides
• Nucleotides have 3 parts
• Phosphate
• Sugar
• Nitrogen base
• Traits are carried in the sequence of nitrogen
  bases
• Common to all organisms

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