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  • DNA
    • What is DNA made of
      • DNA is strands of polymers made up of Nucleotides
        • Each nucleotide consists of one sugar molecule, on phosphate molecule and one base. This makes the backbone of the DNA
        • There are four different bases joins to each sugar, A(adenine),T(thymine),C(cytosine),G(guanine)
          • A always joins up with T and C always joins up with G to form a weak hydrogen bond
    • Chromosomes are long, coiled up molecules in DNA. They are found in the nucleus. A gene is a section of the DNA controlling a particular protein
    • Extracting DNA
      • Add some ice-cold alcohol to the filtered mixture
      • Filter the mixture to get the froth and insoluble bits out
      • The DNA will start to come out as its not soluble with cold Alcohol.
        • It will appear as a stringy white precipitate
      • Mash some strawberries and put in a beaker with detergent and salt
        • The salt helps bind the DNA
        • The detergent breaks down the cell membranes to release the DNA
    • Hydrogen bonding
      • A slightly negative charged part of one base attracts positively charged part of another base. This forms a weak hydrogen bond
      • C and G form three hydrogen bonds and A and T only form two explaining why the pairs only pair with the partner


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