Some bacteria live in the soil or on dead plant matter where they play an important role in the cycling of nutrients. Some types cause food spoilage and crop damage but others are incredibly useful in the production of fermented foods such as yoghurt and soy sauce. Relatively few bacteria are parasites or pathogens that cause disease in animals and plants. Bacteria reproduce by binary fission. In this process the bacterium, which is a single cell, divides into two identical daughter cells.
Binary fission begins when the DNA of the bacterium divides into two replicates. The bacterial cell then elongates and splits into two daughter cells each with identical DNA to the parent cell. Each daughter cell is a clone of the parent cell. When conditions are favourable such as the right temperature and nutrients are available, some bacteria like Escherichia coli can divide every 20 minutes.
This means that in just seven hours one bacterium can generate 2,, bacteria. After one more hour the number of bacteria will have risen to a colossal 16,, Some bacteria can form endospores. These are dormant structures, which are extremely resistant to hostile physical and chemical conditions such as heat, UV radiation and disinfectants.
But, to remain viable and competitive, a bacterium must divide at the right time, in the right place, and must provide each offspring with a complete copy of its essential genetic material. Bacterial cell division is studied in many research laboratories throughout the world.
These investigations are uncovering the genetic mechanisms that regulate and drive bacterial cell division. Understanding the mechanics of this process is of great interest because it may allow for the design of new chemicals or novel antibiotics that specifically target and interfere with cell division in bacteria.
Before binary fission occurs, the cell must copy its genetic material DNA and segregate these copies to opposite ends of the cell. Then the many types of proteins that comprise the cell division machinery assemble at the future division site. A key component of this machinery is the protein FtsZ. Protein monomers of FtsZ assemble into a ring-like structure at the center of a cell.
Other components of the division apparatus then assemble at the FtsZ ring. This machinery is positioned so that division splits the cytoplasm and does not damage DNA in the process. As division occurs, the cytoplasm is cleaved in two, and in many bacteria, new cell wall is synthesized. The order and timing of these processes DNA replication, DNA segregation, division site selection, invagination of the cell envelope and synthesis of new cell wall are tightly controlled.
There are groups of bacteria that use unusual forms or patterns of cell division to reproduce. Some of these bacteria grow to more than twice their starting cell size and then use multiple divisions to produce multiple offspring cells. Updated October 12, Key Takeaways Binary fission is the process by which a single cell divides to form two cells that are genetically identical to one another. There are three common bacterial cell shapes: rod-shaped, spherical, and spiral.
Common bacterial cell components include: a cell wall, a cellular membrane, the cytoplasm, flagella, a nucleoid region, plasmids as well as ribosomes. Binary fission as a means of reproduction has a number of benefits, chief among them is the ability to reproduce in high numbers at a very rapid rate. Since binary fission produces identical cells, bacteria can become more genetically varied through recombination, which involves the transfer of genes between cells.
Featured Video. Cite this Article Format. Bailey, Regina. Bacterial Reproduction and Binary Fission. What Are Prokaryotic Cells? Structure, Function, and Definition. Differences Between Bacteria and Viruses. Learn About Amoeba Anatomy and Reproduction. The Structure and Function of a Cell Wall. Your Privacy Rights. To change or withdraw your consent choices for ThoughtCo. At any time, you can update your settings through the "EU Privacy" link at the bottom of any page. These choices will be signaled globally to our partners and will not affect browsing data.
We and our partners process data to: Actively scan device characteristics for identification. A single bacterium can contain hundreds of replicated plasmids.
Bacteria are extremely diverse, and some forms of bacteria don't replicate through binary fission. The cyanobacteria Stanieria replicates within the cell wall, producing dozens or even hundreds of offspring called baeocytes. The cell wall ruptures, and all the baeocytes are released simultaneously. In Epulopiscium, two small offspring cells form from the replicated DNA within a larger mother cell.
When the offspring are fully developed, the mother cell dies, releasing two complete bacteria cells. A reproductive process called budding has also been observed in some members of the Planctomycetes, but the mechanics of this process are still unknown. Max Roman Dilthey is a science, health and culture writer currently pursuing a master's of sustainability science.
Based in Massachusetts, he blogs about cycling at MaxTheCyclist. Three Mechanisms of Genetic Recombination in Prokaryotes.
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