Question

How do prokaryotic cells divide by binary fission?

Answer 1

Hint: A method of reproduction used by prokaryotes to create cells that are a copy of themselves is called binary fission.

Complete answer:
Binary fission is a method of asexual reproduction where a prokaryotic cell-like bacteria divides to form two identical cells. It a fast process and requires only one parent. It occurs in the domain Archaea and Bacteria. These domains have prokaryotic cells. Prokaryotic cells lack a true nucleus and membrane-bound organelles. They are unicellular and contain singular chromosomes.
It also occurs in eukaryotic organisms for the duplication of cellular organelles like- mitochondria.

The process of binary fission occurs in four steps-
1)Replication of DNA- The genetic material or DNA of bacteria is singular and coiled in a circular manner. It is present in the nucleoid of the cell. The nucleoid is an irregular-shaped region without a nuclear membrane. They also have plasmids that are small, circular extrachromosomal DNA capable of independent division.
2)The genetic material of bacteria unwinds- and gives access to some special proteins. These proteins start the process of replication at a site called the origin of replication, from where it moves to the two opposite ends.
3)Growth of a cell- Once the replication of DNA finishes and the genetic material is- doubled, cell growth occurs. The cytoplasm of the cell increases- and the cell size grows.
4)Segregation of DNA- The replicated genetic material separates and moves towards the opposite ends when the cell membrane pinches off and forms a septum.
5)Splitting of cells- The septum elongates, and a new cell wall is formed. The splitting of the septum along with the movement of necessary proteins to the opposite ends occurs- resulting in the formation of two daughter cells.

These two daughter cells have their genetic material and necessary proteins required for their independent survival. They are genetically and morphologically similar to each other and also called- clones.
Prokaryotes use binary fission as a mode of asexual reproduction, whereas eukaryotic organisms use it as a mode to replicate their organelles.

Note: The process of binary fission is often compared to mitosis. The former here is a simple and fast process that occurs in the prokaryotic organisms. It has no sub-phases and does not include specialized and complex organelles.
Mitosis is a complex and slow process with four sub-phases and occurs in eukaryotic organisms. It includes specialized organelles like spindle apparatus. It is a nuclear division that produces genetically identical cells.