Molecular Basis of Inheritance Question 54
54. During DNA replication, Okazaki fragments are used to elongate:
[2017]
(a) The lagging strand towards replication fork.
(b) The leading strand away from replication fork.
(c) The lagging strand away from the replication fork.
(d) The leading strand towards replication fork.
Show Answer
Answer : c
Hints & Solution
(c) Two DNA polymerase molecules simultaneously work at the DNA fork, one on the leading strand and the other on the lagging strand. DNA polymerase synthesizes each Okazaki fragment at lagging strand in $5^{\prime}-3^{\prime}$ direction. As the replication fork opens further, new Okazaki fragments appear. The first Okazaki fragment appears away from the replication fork and thus the direction of elongation would be away from replication fork.
