DNA replication in E.coli What is the difference between replication and to divide? My A level bio book says that it takes 20 min for _E.coli_ to divide and in next page it's written that _E.coli_ completes replication within 38min. Moreover, there is a diagram (shown below) which contradicts as what I thought. Please explain the difference between replication and division. ![enter image description here](

I am unsure if I really understand the question. Are you wondering how the rate of DNA replication can be slower than the rate of cell division if every daughter cell needs a chromosome copy?

If so, keep in mind that prokaryotes have different origins of replication on their chromosome so that **DNA replication can actually be parallelised**. Cooper (1968) presents a mathematical model that is consistent with experimental findings and indicates that when the DNA replication step becomes limiting for cell division, _E. coli_ switches to multiple replication forks, thus decreasing the net time needed for complete DNA replication.

According to that, it is no contradiction that DNA replication _per se_ takes longer than cell division.