2. DNA structure.notebook
May 12, 2015
DNA structure
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2. DNA structure.notebook
May 12, 2015
The building blocks of DNA are nucleotides
Nucleotides are made up of three things
1. A phosphate group
2. A sugar, deoxyribose
3. A base (A, C, G, T)
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2. DNA structure.notebook
May 12, 2015
1. Phosphate group
contains phosphorous and oxygen atoms
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2. DNA structure.notebook
May 12, 2015
2. Deoxyribose sugar
a pentose (think pentagon) sugar
5 carbon atoms phosphate group can only attach to the 5th carbon and the 3rd don't worry about the number of carbons and where things attach
this causes the two strands to run in different directions (anti­parallel) ­ will talk about this later
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2. DNA structure.notebook
May 12, 2015
3. One of 4 bases
There are 4 possible bases
A ­ Adenine
T ­ Thymine
C ­ Cytosine
G ­ Guanine
bases are held together by hydrogen bonds ­ if the hydrogen bonds break, the two strands come apart
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2. DNA structure.notebook
May 12, 2015
Together they make a nucleotide
Lots of nucleotides make up DNA
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2. DNA structure.notebook
May 12, 2015
The complimentary base­pairing rule
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2. DNA structure.notebook
May 12, 2015
So far we have learned...
All cells need DNA (last lesson)
DNA is made up of nucleotides
Nucleotides consist of 3 things
phosphate/sugar/base
The complimentary base­pairing rule means that T can only bond with A and C can only bond with G
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2. DNA structure.notebook
May 12, 2015
A DNA molecule consists of two chains of nucleotides arranged in a spiral shape called a double helix
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2. DNA structure.notebook
May 12, 2015
The two strands of nucleotides run anti­parallel to each other
this is due to the order of the carbons on the sugar molecule (you won't need to know this until L2 bio)
just know that the two strands run anti­parallel to each other
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2. DNA structure.notebook
May 12, 2015
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2. DNA structure.notebook
May 12, 2015
Your task pair up, or work solo
use playdough to construct an accurate model of a DNA molecule
You must illustrate the complimentary base­pairing rule, antiparallel strands and demonstrate good labelling skills
Take a picture, upload it to your WD, instagram it if you want #biowithej #bioatdio +anything else
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