image/svg+xml
A
P
P
P
P
P
P
P
P
G
C
P
A
T
G
A
T
C
C
G
P
P
C
A
P
G
P
G
P
P
T
P
P
P
DNA polymerase
5'
3'
5'
3'
Extension
P
P
P
P
P
P
P
P
G
C
P
A
T
G
A
T
C
C
G
P
P
C
A
P
G
P
G
P
P
T
P
P
P
5'
3'
5'
3'
P
P
P
A
Extension
P
P
P
P
P
P
P
P
G
C
P
A
T
G
A
T
C
C
G
P
P
C
A
P
G
P
G
P
P
T
P
5'
3'
5'
3'
P
(error)
Proofreading
P
P
P
P
P
P
P
P
G
C
P
A
T
G
A
T
C
C
G
P
P
C
A
P
G
P
G
P
P
T
P
5'
3'
5'
3'
A
P
Extension
P
P
P
P
P
P
P
P
G
C
P
A
T
G
A
T
C
C
G
P
P
C
A
P
G
P
G
P
P
T
P
5'
3'
5'
3'
P
G
P
P
P
G
nucleosidetriphosphate
P
P
P
P