3. a mental representation of something: she's got a good idea of the layout of the factory. 4. the characterization of something in general terms; concept: the idea of a square circle is self-contradictory. 5. an individual's conception of something: his idea of honesty is not the same as yours and mine. 6. the belief that something is the case: he has the idea that what he's doing is right. 7. a scheme, intention, plan, etc: here's my idea for the sales campaign. 8. a vague notion or indication; inkling: he had no idea of what life would be like in Africa.
Since DNA replication moves along the parent strand in the 5' to 3' direction, replication can occur very easily on the leading strand. As seen in, the nucleotides are added in the 5' to 3' direction. Triggered by RNA primase, which adds the first nucleotide to the nascent chain, the DNA polymerase simply sits near the replication fork, moving as the fork does, adding nucleotides one after the other, preserving the proper anti-parallel orientation.
In summary, DNA replication is the process of making copies of DNA. DNA replicates by semi-conservative replication, which means that one strand of the parent double helix is conserved in each new DNA molecule. Meselson and Stahl were the scientists who showed that DNA follows the semi-conservative model.