Question

Which of the following accurately describes the direction of DNA synthesis?

A. 5' to 3' on both template and synthesized strands
B. 3' to 5' on the template strand and 5' to 3' on the synthesized strand
C. 5' to 3' on the template strand and 3' to 5' on the synthesized strand
D. It depends on whether the DNA is found in prokaryotes or eukaryotes.
E. 3' to 5' on both template and synthesized strands

Answer 1

DNA synthesis occurs in the direction of 3' to 5' on the template strand and 5' to 3' on the synthesized strand, with continuous synthesis on the leading strand and segmented synthesis on the lagging strand in the form of Okazaki fragments.

Step-by-step explanation:

The correct answer to the question of which description accurately reflects the direction of DNA synthesis is B. 3' to 5' on the template strand and 5' to 3' on the synthesized strand. During DNA replication, the enzyme DNA polymerase reads the template strand in the 3' to 5' direction and adds nucleotides to the synthesized strand in the 5' to 3' direction.

The continuously synthesized strand that moves towards the replication fork is known as the leading strand. In contrast, the lagging strand is synthesized in Okazaki fragments, which are short stretches of DNA extended away from the replication fork.

This process is consistent across both prokaryotes and eukaryotes, indicating that the direction of synthesis does not depend on the type of organism. Instead, the antiparallel nature of DNA strands dictates that while one strand can be synthesized continuously, the other must be extended in segments as the replication machinery moves along the template.