二元裂变

Prokaryotes propagate via cell division, albeit by using a different process than eukaryotes, one that's asexual, forming two genetically identical clones of itself. This type of reproduction is termed binary fission, meaning division in half.

To divide, the cell first replaces its DNA, copying the chromosome from its origin of replication, an area near chromosomal contact with the cell plasma membrane. Replication enzymes copy the chromosome bidirectionally, moving in opposite directions from the origin to create two double-stranded chromosomes.

As replication occurs, both chromosomes begin to move away from each other, to opposite sides of the cell. The cell itself lengthens, spurring chromosomal or nucleoid separation.

Once the chromosomes have moved to opposite sides, cytoplasmic separation, cytokinesis can begin. Now a ring of self-assembling proteins forms at the cell midpoint, directing the formation of a septum ring, a developing cell wall from the midpoint peripheries to the middle.

When the septum is finished developing, it pinches off the cell, splitting to yield two identical daughter cells.