Download 8.1-8.2 TAKE DOWN NOTES AND SKETCH MOLECULES

8.1-8.2 TAKE DOWN NOTES AND SKETCH MOLECULES
DNA was identified as the genetic material through a series
of experiments.
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Griffith used bacteria to find the “transforming principle”
that would be identified by Avery as DNA.
Deoxyribonucleic Acid– DNA has two strands and is a
double helix.
Hershey & Chase confirmed that DNA is the material that
passes on traits.
Epigenetics– our genes can be “tagged” to turn on or off.
They can be expressed differently by these tags.
We believe epigenetic tags can be controlled by disease,
nutrition and lifestyle choice.
Chargoff found 4 bases in DNA
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Adenine ——> Thymine
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Guanine ——> Cytosine
Watson & Crick discovered the double helix shape
with help from Rosalind Franklin and Maurice Wilkins
*We will go over the movie answers…..just hold onto them.
DNA is composed of NUCLEOTIDES that are repeating
units….running anti-parallel to each other.
The Nitrogenous bases are in two groups:
PYRIMIDINES = Single Ring
Thymine & Cytosine
PURINES = Double Ring
Guanine & Adenine
Nitrogenous bases are bonded by Hydrogen Bonds
Sugars have Covalent bonds to phophates and bases
Covalent
Covalent
Hydrogen
Guanine and Cytosine have TRIPLE HYDROGEN bonds
Thymine and Adenine have DOUBLE HYDROGEN bonds