Question

The elongation of the leading strand during DNA synthesis

A) progresses away from the replication fork.
B) occurs in the 3' → 5' direction.
C) produces Okazaki fragments.
D) depends on the action of DNA polymerase.
E) does not require a template strand.

Answer 1

The elongation of the leading strand during DNA synthesis occurs in the direction away from the replication fork and depends on the action of DNA polymerase.

Step-by-step explanation:

The elongation of the leading strand during DNA synthesis occurs in the direction away from the replication fork, which is option A. Option B is incorrect because DNA polymerase reads the template strand in the 3' to 5' direction and adds nucleotides only in the 5' to 3' direction. Option C is incorrect because Okazaki fragments are produced during replication on the lagging strand, not the leading strand. Option E is also incorrect because the leading strand does require a template strand. The correct answer is option D, which states that the elongation of the leading strand depends on the action of DNA polymerase.

Answer 2

The only correct one is D - depends on the action of DNA polymerase.

A - no progresses towards the replication fork (the "fork" opens up as elongation moves towards it)

B - the DNA template is READ in the 3' - 5' direction, but it is BUILT in the 5' - 3' direction

C - Okazaki fragments are only made on the lagging strand (because it is hard to make the DNA on that strand

D - YEP

E - Absolutely requires a template strand (otherwise we wouldn't exist!)