3. The enzyme DNA polymerase works only in the 5' to 3' direction. How does this affect the leading strand and the lagging strand?

A. DNA polymerase can work on both the leading and the lagging strand but is much faster on the leading strand.

B. DNA polymerase can use only the leading strand as a template. A different enzyme is used to synthesize DNA on the lagging strand.

C. DNA polymerase can work continuously on the leading strand but works discontinuously on the lagging strand, creating Okazaki fragments.

D. DNA polymerase can work continuously on the leading strand but must flip the lagging strand around before it can work on it.

Answer: C

DNA polymerase can work continuously on the leading strand and works discontinuously on the lagging strand creating okazaki fragments.

Explanation:

The strands of DNA are anti parallel. One strand has the polarity 5I → 3I and the other has the polarity 3I → 5I. Thus DNA replication is not similar in these two strands. DNA replication is the function of the enzyme DNA polymerase and it synthesizes DNA strand having polarity 5I → 3I continuously while the other copy is discontinuous with fragments called okazaki fragments.

Both strands of DNA act as templates and the strand which is replicated continuously is called leading strand and the other which is discontinuously replicated forming okazaki fragments is called lagging strand.