Final answer:
The accurate terms that reflect the nature of replication of the chromosome in E. coli are bidirectional and fixed point of initiation. In E. coli, replication begins at a specific nucleotide sequence called the origin of replication, and two replication forks are formed at this origin to replicate in both directions. Option 1 is correct..
Step-by-step explanation:
The accurate terms that reflect the nature of replication of the chromosome in E. coli are bidirectional and fixed point of initiation.In E. coli, replication begins at a specific nucleotide sequence called the origin of replication, which is recognized by certain proteins. The enzyme helicase unwinds the DNA, and Y-shaped structures called replication forks are formed. Two replication forks are formed at the origin of replication and replicate in both directions.
This bidirectional replication process ensures that the entire chromosome is replicated efficiently. The process by which E. coli replicates its chromosome is well-understood. Replication begins at a single origin of replication on its circular chromosome and proceeds bidirectionally, meaning that it occurs in both directions away from the origin. This process is highly efficient, with about 1000 nucleotides being added every second. As a result, E. coli can replicate its entire genome of 4.6 million base pairs in approximately 42 minutes. Such bidirectional replication is a key characteristic that differentiates prokaryotic DNA replication from eukaryotic replication, the latter often having multiple origins of replication.