Open Question
What would be the effects on DNA replication if mutation of DNA pol III caused it to lose each of the following activities?
5' to 3' polymerase activity
8. DNA Replication
Overview of DNA Replication
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Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
DNA replication synthesizes DNA in which direction?
A
5' to 3'
B
3' to 5'
C
Leading strand 5' to 3', lagging strand 3' to 5'
D
Leading strand 3' to 5', lagging strand 5' to 3'
Verified step by step guidance1
Understand the basic structure of DNA: DNA strands have directionality, with one end labeled 5' (five prime) and the other 3' (three prime). This is based on the numbering of carbon atoms in the deoxyribose sugar of the DNA backbone.
Recognize that DNA replication involves the synthesis of a new strand complementary to the template strand. DNA polymerases, the enzymes responsible for DNA synthesis, can only add nucleotides to the 3' end of a growing DNA strand.
Identify the direction of DNA synthesis: Since DNA polymerases add nucleotides to the 3' end, DNA synthesis occurs in the 5' to 3' direction.
Differentiate between the leading and lagging strands: During replication, the leading strand is synthesized continuously in the 5' to 3' direction, while the lagging strand is synthesized discontinuously in short segments called Okazaki fragments, also in the 5' to 3' direction.
Clarify the misconception: Although the lagging strand is synthesized in segments, each segment is still synthesized in the 5' to 3' direction. The overall process involves the replication fork moving in the 3' to 5' direction relative to the lagging strand template, but synthesis itself is always 5' to 3'.
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Overview of DNA Replication practice set
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