Final answer:
DNA replication in eukaryotic linear chromosomes begins at multiple sites called origins of replication, which are recognized by specific proteins that initiate the replication process.
Step-by-step explanation:
DNA replication of linear chromosomes is initiated at multiple sites known as origins of replication. In eukaryotes, there are multiple linear chromosomes, each with multiple origins allowing simultaneous replication from several places in the genome. Unlike prokaryotes, such as E. coli, which have a single, circular chromosome with a single origin of replication, eukaryotic chromosomes are equipped with multiple replication sites due to their higher complexity and size.
During initiation, proteins bind to these origins and an enzyme called helicase unwinds the DNA helix, forming Y-shaped structures called replication forks. These forks then extend in both directions as replication proceeds. This process requires a series of enzymes and proteins that recognize the specific nucleotide sequences of the origins to begin DNA synthesis accurately.