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  #1  
Old 08-05-2011
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Default genetics

A substantial portion of single nucleotide substitution causing human genetic disease are due misincorporation of bases during DNA replication.
which proof-reading activity is critical in determining the accuracy of nuclear DNA replication and thus the base substitution mutation rate in human chromosome ?

a)3' to 5' polymerase activity of DNA polymerase DELTA
b)3'to 5' exonuclease activity of DNA polymerase GAMMA
c)primase activity of DNA polymerase ALPHA
d)5' to 3' polymerase activity of DNA polymerase III
e)3' to 5' exonuclease activity of DNA polymerase DELTA
f)DNA ligase
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Old 08-05-2011
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Default B or E

Either B or E, a 5->3 exonuclease activity allows for DNA repair during DNA synthesis if there's a mismatch. I'll just guess this one out and say B.
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Old 08-05-2011
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Quote:
Originally Posted by IKR123 View Post
A substantial portion of single nucleotide substitution causing human genetic disease are due misincorporation of bases during DNA replication.
which proof-reading activity is critical in determining the accuracy of nuclear DNA replication and thus the base substitution mutation rate in human chromosome ?

a)3' to 5' polymerase activity of DNA polymerase DELTA
b)3'to 5' exonuclease activity of DNA polymerase GAMMA
c)primase activity of DNA polymerase ALPHA
d)5' to 3' polymerase activity of DNA polymerase III
e)3' to 5' exonuclease activity of DNA polymerase DELTA
f)DNA ligase
answr is E....bcoz DNA POLYMERASE ALPHA+DELTA are human dna polymerases!!!!!
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  #4  
Old 08-05-2011
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Quote:
Originally Posted by IKR123 View Post
A substantial portion of single nucleotide substitution causing human genetic disease are due misincorporation of bases during DNA replication.
which proof-reading activity is critical in determining the accuracy of nuclear DNA replication and thus the base substitution mutation rate in human chromosome ?

a)3' to 5' polymerase activity of DNA polymerase DELTA
b)3'to 5' exonuclease activity of DNA polymerase GAMMA
c)primase activity of DNA polymerase ALPHA
d)5' to 3' polymerase activity of DNA polymerase III
e)3' to 5' exonuclease activity of DNA polymerase DELTA
f)DNA ligase
e)3' to 5' exonuclease activity of DNA polymerase DELTA
i think its e, because, it is a human model soo dna polymerase III is nt there....what is there is dna polymerase delta, in prokaryots dna polymerase III cause synthesis in 5`-3` direction and proof reading in the opp so as it is a human model ill go with( e )
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Old 08-05-2011
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e)3' to 5' exonuclease activity of DNA polymerase DELTA

Reads from 3' to 5' and makes nucleotides in 5' to 3' when makes a mistakews it stops then turns back and Chops 3' to 5' Phosphodiesterase bond
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