(a) Why does DNA replication occur in small replication forks and not in its entire length ?
(b) why is DNA replication continuous and discontinuous in a replication fork ?
(c) State the importance of origin of replication in a replication fork.

Explanation

(a) DNA is a macromolecule since two strands of DNA cannot be separated in its entire length (due to very high energy requirement), the replication occur in small replication fork.
(b) The DNA-dependent DNA polymerases catalyse polymerization only in one direction, that is 5'-3'.
This creates some additional complications at the replicating fork. On one strand (the template with polarity 3'-5') , the replication is continuous, while on the other (the template with polarity 5'-3'), it is discontinuous.
(c) This is the region from where the DNA replication is initiated.