1. DNA Deoxyribonucleic acid What is it??? DNA is a biomolecule
it contains your
“genetic code”
(instructions for all inherited traits)

2. DNA DNA is made of….. 3 parts of a nucleotide: 1. 2. 3. ….nucleotides
Phosphate group
A sugar, called deoxyribose
….nucleotides
A nitrogenous base such as:
Adenine
Thymine
Cytosine
Guanine

3. DNA
The nucleotides join together to make a double stranded molecule of DNA (double helix).
-What connects the nucleotides?
-Which part of the nucleotide makes up the “backbone” of the DNA?
-Which part of the nucleotide contains your “code” for inherited traits?
Hydrogen bonds
Phosphate and sugar
The order of the nitrogen bases

4. Chagraff’s base-pair rule
Adenine pairs with Thymine
and
Cytosine pairs with Guanine
% of Adenine = % of Thymine
% of Cytosine = % of Guanine
If there is 20% Adenine, what percent thymine?
what percent cytosine?
what percent guanine?
20%
30%

5. Try this….. If one strand of DNA contains this code……
ATC GGC CAT TGC CCA AAG CGA TCA
TAG CCG GTA ACG GGT TTC GCA AGT
The other strand would be….

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