At DNA replication forks, the overall growth of the antiparallel two daughter 
DNA chains appears to occur 5'-to-3' direction in the leading-strand and 
3'-to-5' direction in the lagging-strand using enzyme system only able to 
elongate 5'-to-3' direction, and I describe in this review how we have analyzed 
and proved the lagging strand multistep synthesis reactions, called 
Discontinuous Replication Mechanism, which involve short RNA primer synthesis, 
primer-dependent short DNA chains (Okazaki fragments) synthesis, primer removal 
from the Okazaki fragments and gap filling between Okazaki fragments by RNase H 
and DNA polymerase I, and long lagging strand formation by joining between 
Okazaki fragments with DNA ligase.