Binary fission

Binary fission is the form of asexual reproduction in single-celled organisms by which one cell divides into two cells of the same size, used by most prokaryotes. Asexual reproduction is a form of reproduction which does not involve Meiosis, Ploidy reduction or Fertilization. The prokaryotes (proʊˈkærioʊts singular prokaryote /proʊˈkæriət/ are a group of Organisms that lack a Cell nucleus (= karyon or any other This process results in the reproduction of a living cell by division into two equal or near-equal parts. The cell is the structural and functional unit of all known living Organisms It is the smallest unit of an organism that is classified as living and is often called

Mitosis is not the same as binary fission. Mitosis is the process in which a Eukaryotic cell separates the Chromosomes in its Cell nucleus, into two identical sets in two daughter nuclei

Genetic effects

Sea anemone in process of cloning (longitudinal fission)

Binary fission is asexual; the organism splits directly into two equal-sized offsprings, each with a copy of the parent's genetic material. Sea anemones are a group of water dwelling predatory animals of the order Actiniaria; they are named after the Anemone, a terrestrial Flower Binary fission is a common type of reproduction in single-celled organisms.

Bacterial DNA has a relatively high mutation rate. In biology mutations are changes to the Nucleotide sequence of the Genetic material of an organism This rapid rate of genetic change is what makes bacteria capable of developing resistance to antibiotics and helps them exploit invasion into a wide range of environments. Antibiotic resistance is the ability of a Microorganism to withstand the effects of Antibiotics.

Organisms that reproduce through binary fission generally have exponential growth phases. Exponential growth (including Exponential decay) occurs when the growth rate of a mathematical function is proportional to the function's current value Escherichia coli cells are able to divide every 20 minutes under optimum conditions.

Process

Animation showing the complete process of binary fission.

Binary fission begins with DNA replication. DNA replication is the process of copying a double-stranded DNA molecule to form two double-stranded molecules DNA replication starts from an origin of replication, which opens up into a replication bubble (note: prokaryotic DNA replication usually has only 1 origin of replication, whereas eukaryotes have multiple origins of replication). The replication bubble separates the DNA double strand, each strand acts as template for synthesis of a daughter strand by semiconservative replication, until the entire prokaryotic DNA is duplicated. Semiconservative replication describes the method by which DNA is replicated in all known cells

After this replicational process, cell growth occurs.

Each circular DNA strand then attaches to the cell membrane. Deoxyribonucleic acid ( DNA) is a Nucleic acid that contains the genetic instructions used in the development and functioning of all known The cell membrane (also called the plasma membrane, plasmalemma, or "phospholipid bilayer" is a Selectively permeable Lipid bilayer The cell elongates, causing the two chromosomes to separate. A chromosome is an organized structure of DNA and Protein that is found in cells.

Cell division in bacteria is controlled by the septal ring, a collection of about a dozen proteins that collect around the site of division. Proteins are large Organic compounds made of Amino acids arranged in a linear chain and joined together by Peptide bonds between the Carboxyl There, they direct assembly of the division septum. the cell wall and plasma membrane starts growing transversely from near the middle of the dividing cell. The dividing septum originates centripetally and separates the parent cell into two nearly equal daughter cells ,each having a nuclear body ^[1]

The cell membrane then invaginates (grows inwards) and splits the cell into two daughter cells, separated by a newly grown cell plate. Invagination means to fold inward or to sheath In Biology, this can refer to a number of processes This process is called cytokinesis. Cytokinesis is the process whereby the Cytoplasm of a single Eukaryotic cell is divided to form two daughter cells

Organisms using binary fission

Many organisms reproduce by binary fission, such as:

• Bacteria
• Protista
• Archaea

Some eukaryotes reproduce using binary fission-like methods. The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have Protists (ˈproʊtɨst are a diverse group of eukaryotic Microorganisms Historically protists were treated as the kingdom Protista but this Cell division is a process by which a cell, called the parent cell divides into two or more cells called daughter cells. Mitosis is thought to derive from binary fission. Mitosis is the process in which a Eukaryotic cell separates the Chromosomes in its Cell nucleus, into two identical sets in two daughter nuclei

Binary fission in protozoans

In binary fission in protozoans, the replicated chromosomes are separated by intranuclear (closed) mitosis and the nucleus divides by furrowing. The cytoplasm then gradually constricts between the two separating nuclei, ultimately forming two equally sized daughter individuals, each with a nucleus. The offspring grows to the size of the parent before dividing again.

Types of binary fission

Binary fission is mainly of three types with regard to the plane of division:

1. Irregular binary fission: Occurs in amoebae. Amoeboids are Unicellular lifeforms that mainly consist of Contractile vacuoles, a nucleus, and cytoplasm as their basic structure The plane of division of cytoplasm varies but is always at right angles to the elongated dividing nucleus.
2. Longitudinal binary fission: Occurs in flagellates such as Euglena. Euglena are a common group of Unicellular Protists, of the class Euglenoidea of the Phylum Euglenophyta. The cytoplasm splits lengthwise, from forward to backward, forming two similar daughter individuals.
3. Transverse binary fission: Occurs in ciliates such as paramecium. The ciliates are one of the most important groups of Protists common almost everywhere there is water — lakes ponds oceans rivers and soils with many ectosymbiotic Paramecia are a group of Unicellular Ciliate Protozoa formerly known as “slipper Animalcules �� from their Slipper shape are commonly The cytoplasm divides transversely between two sets of nuclei, forming two dissimilar individuals. This is called bacterial fission.

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