Binary Fission in Amoeba and Bacteria – Imaluop

Now we will discuss a special mode of reproduction: binary fission in amoeba and bacteria which are responsible for their very high rate of multiplication and this mode of reproduction makes them immortal. 

What is Binary Fission: 

Binary fission is a very primitive mode of reproduction which was present from the origin of different lower organisms present on our earth during the origin of life on our earth. It is a method of division of most of the unicellular prokaryotes and some unicellular eukaryotes where the genetic material is divided into two copies by the method of DNA replication and each copy gives rise to a new individual.  

The individual new organisms formed after the process of binary fission produce two genetically similar organisms because here the crossing over is absent so the variation is absent until any mutation occurs in the DNA.  

Binary fission is common in bacteria and the function of antibiotics is based on the genetic similarities of all bacteria cells because if a strain of bacteria affected by a specific antibiotics then all the bacteria of the strain will also affected by the antibiotics but when a mutation occurs in any bacteria cell then the bacteria formed from the mutant bacteria cell can show antibiotics resistance.  

Binary fission is the primary method of reproduction in prokaryotic organisms like bacteria Escherichia Coli and archaebacteria but it is also present in some eukaryotic organisms like Amoeba and Euglena.  

Binary Fission in Amoeba: 

Amoeba is a eukaryotic unicellular protist in which a mode of reproduction is binary fission where the genetic material first doubles through the process of DNA replication. When the replication process completed the single genome converted into two copies of genome and then the Amoeba form two nucleus and cytoplasm also start to divide into two parts.

Each part form a new individual and so it able the organism to multiply at very high rate and the two individuals become the copy of the parent Amoeba cell so we can say the Amoeba is immortal because the cell do not die only divide into two.  

Binary Fission in Bacteria: 

Primary mode of reproduction in different prokaryotes especially in archaebacteria is binary fission. Binary fission in a bacterial colony doubles the number of bacteria and the time required for doubling the number of bacteria through the process of binary fission is called doubling time and it is different in different species.

The time required for doubling the number is dependent on some factors like the pH of the medium, temperature, nutrients availability, oxygen availability and osmotic pressure of the outer environment.

For example in case of Escherichia Coli the doubling time is around 20 minutes so they only take 20 minutes to divide by the process of binary fission but in some cases it is much longer as seen in the case of Mycobacterium Tuberculosis which takes around 20 hours to divide by the process of binary fission at optimum conditions.

Now we will discuss different stages that take place during the division of bacteria by the process of binary fission below. 

Replication of DNA: 

First step of binary fission is doubling the genetic material by the process of DNA replication which makes two copies of genetic material because two individual cells require one copy of DNA as a genetic material. 

Cell Growth: 

After the replication the bacteria cells start to grow to increase the cytoplasmic content of the cell because the two individual bacteria cells need cytoplasm along with the genetic material. 

Separation of Two Copies of DNA: 

Inside the bacterial cell the two copies of DNA move apart and separate meanwhile the cell forms a separation between the two copies. 

Splitting of Bacteria Cell: 

A cell wall formed in between the two DNA copies divides the cell into two daughter cells with each daughter cell having a copy of DNA along with cytoplasm and other essential cell organelles. 

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