Binary fission

Introduction 

A cell replicates its DNA during binary fission and separates into two daughter cells. After mitosis, each cell has a copy of the parent DNA. For example; amoeba, bacteria and most single-celled creatures follow this mechanism.

Binary fission might be as old as life itself, dating back over 3.5 billion years. Since then, the procedure has remained unaltered.

Definition of Binary Fission

Binary fission definition is an asexual reproductive method occur in prokaryotes and a few single-celled eukaryotes(Amoeba) . The parent cell is divided into two new daughter cells in binary fission.It is a type of reproduction in which nuclear division is followed by the appearance of a constriction in the cell membrane, which gradually deepens inward and divides the cytoplasm into two parts, each with one nucleus. Finally two daughter cells are formed. 

In prokaryotic organisms, it is the most common way of reproduction. Binary fusion occurs in the absence of a spindle apparatus in the cell. Instead, the single DNA molecule starts replication and then binds each duplicate to different sections of the cell membrane in this process. As a result, the original (real) and duplicated chromosomes separate when the cell begins to be dragged apart.

However, there is a substantial disadvantage to asexual reproduction. All offspring are genetically identical to each other and the parent cell.

This is how the majority of antibiotics operate. If a parent cell is susceptible to an antibiotic, all daughter cells will also be. If a mutation occurs in their genome, a specific strain can become antibiotic-resistant.

Binary fission is how prokaryotes like E. coli and Archaea and eukaryotes like Euglena reproduce.

Process of binary fission 

• Step 1: Replication of DNA

Because binary fission takes place in prokaryotic cells, it is an easy and quick approach with a wide range of properties. Because prokaryotic cells lack a nucleus, genetic information or DNA is stored in a region known as the nucleoid. Which, in turn, comprises a single chromosome containing all of a living being’s genetic data. The binary fission procedure occurs on this chromosome and inside it is the component of the origin of replication, where the DNA is replicated.

• Step 2: Growth of Cell

As a result, when genetic material has already been replicated and separated, two new origins are created, splitting at each chromosome’s end until they fall off. As a result, two new chromosomes with identical genetic load emerge from the similar stem cell, and then the cell grows.

• Step 3: Isolation of DNA

DNA along with plasmids have been replicated. Different regions of the cell membrane hold individual copies of DNA. DNA molecules are moved to various cell sides when they elongate in preparation for multiplication.

• Step 4: Cleavage

As the cell wall and membrane start to press and generate two new cells, a cleavage groove emerges in the cell membrane. 

Finally, the cells entirely separate as a new bacterial cell wall develops. Further, the breaking down of any remaining proteins or other molecules that link the two cells also takes place in this stage. As a result, every cell now has all it requires to carry on the functions of life on its own. The entire procedure can be completed in as little as 15 minutes in certain species. On the other hand, others can reproduce at lesser rates.

Types of Binary Fission

Binary fission is divided into different categories, each distinguished by the method of cell division. Each of these distinctions is critical in determining the form and size of these creatures.

• Simple binary fission happens when a cell splits symmetrically, resulting in two identical new creatures. Amoebas are a good example.

• Transverse binary fission: The cell divides in lockstep with the organism’s transverse axis due to binary fission, as in the case of the planar creature. E.g-Paramecium

• Longitudinal binary fission: The splitting of the body occurs along the direction of the organism’s longitudinal axis. In the instance of Euglena, this is the case.

• Multiple binary fission: Bipartition does not have a specific form in organisms because it occurs in various ways. Furthermore, the nucleus of this sort of creature is not separated into two sections. As a result of the nucleus becoming fractionated, the cytoplasm divides. A cell can give rise to many different cells, like malaria Protozoans(Plasmodium), which can develop or occupy a body more than any other microorganism. E.g-Plasmodium, Sporozoans, Algae

Examples of Binary fission

This form of reproduction may be seen in a lot of places. For example, it is used by most bacterial organisms and certain eukaryotes. Here are a few binary fission examples:

1. Binary Fission in Bacteria

Binary fission is a fast process that varies in speed depending on the species. For example, the amount of time it takes bacteria to double their number of cells is known as doubling time. Additionally, each species has its own set of circumstances to thrive. pH levels, temperature, oxygen, light, moisture and osmotic pressure are examples of these circumstances.

Mesophiles, for example, survive in temperatures ranging from 20 to 45℃. Because the human body’s ambient temperature is 37℃, many disease-causing microorganisms are mesophiles. For example, the bacteria that causes TB in humans is Mycobacterium tuberculosis. Compared to other harmful bacteria such as Escherichia coli, which multiplies every 20 minutes, it divides every 15 to 20 hours.

Extremophiles are on the other extreme of the spectrum. Extremely hard circumstances, such as high salinity, highly acidic environments, and high temperatures, are no match for these bacteria. For example, the extremophilic bacterium Deinococcus radiodurans can withstand a thousand times the amount of radiation that a human can. It can split every 48 hours in normal circumstances. When faced with adversity, such as drought, it might slow down its development rate until more favorable conditions emerge.

2. Binary Fission in Amoeba

Amoeba is a single-celled creature easily reproduced by binary fission, exactly like bacteria. After mitotic division replicates its genetic material, the cell quickly splits into two equal-sized daughter cells. Two identical people are always made from a single-parent cell in this approach. An amoeba on the verge of division becomes bigger and then the nucleus stretches and separates into two. The division of the cytoplasm follows the division of the nucleus. So, two amoebae are created from a single parent, and the parent’s identification is technically “end up losing.”

Conclusion

To ensure the survival of their species, all living creatures are capable of creating progeny. Less complicated animals use asexual reproduction as a mechanism of passing on their genes.

Because they possess identical genetic material, binary fission usually creates cells with the same genetic identity (assuming there were no random mutations).

However, because this procedure can be completed rapidly, it is efficient. Furthermore, binary fission preserves the parent cell’s identity, which might aid rapid population increase, providing limited space for genetic mutation or adaptation.