Rungs
Rungs
� adenine
thymine
adenine
thymine
�
�
�
�
�
�
�
�
�
�
© CSIRO’s Double Helix Science Club
�
© CSIRO’s Double Helix Science Club
�
�
�
�
�
�
�
�
�
�
�
�
�
� guanine
�
�
�
�
��
��
��
��
� guanine
cytosine
© CSIRO’s Double Helix Science Club
cytosine
�
© CSIRO’s Double Helix Science Club
��
��
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A DNA molecule from
CSIRO’s
A DNA molecule from
CSIRO’s
http://www.csiro.au/helix
http://www.csiro.au/helix
© CSIRO’s Double Helix Science Club
© CSIRO’s Double Helix Science Club
P
P
P
P
P
P
P
P
P
P
P
13
12
10
8
7
6
5
4
P
2
S
S
9
S
S
3
1
© CSIRO’s Double Helix Science Club
S
11
P
S
S
S
S
S
S
S
S
S
P
P
P
P
P
P
P
P
P
P
P
P
© CSIRO’s Double Helix Science Club
14
13
12
10
8
7
6
5
4
P
2
S
S
9
S
S
3
1
© CSIRO’s Double Helix Science Club
P
© CSIRO’s Double Helix Science Club
P
14
Spine A
Spine B
Spine A
S
S
11
S
S
S
S
S
S
S
S
Spine B
S
P
S
P
1
1
S
P
S
P
2
2
S
P
S
P
3
3
S
P
S
P
4
4
S
P
S
P
S
P
S
S
5
5
7
P
7
P
S
P
S
P
S
P
S
P
8
8
6
6
9
9
S
P
S
P
S
P
S
10
10
S
P
11
P
S
S
P
11
12
P
12
13
13
S
P
S
P
S
P
S
P
14
14