The Full Wiki

Binary fission: Wikis

  

Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! This article doesn't yet, but we're working on it! See more info or our list of citable articles.

Encyclopedia

From Wikipedia, the free encyclopedia

Binary fission

Binary fission, or prokaryotic fission, is the form of asexual reproduction and cell division used by all prokaryotes, some protozoa, and some organelles within eukaryotic organisms. This process results in the reproduction of a living prokaryotic cell by division into two parts which each have the potential to grow to the size of the original cell.

Mitosis and cytokinesis are not the same as binary fission; specifically, binary fission cannot be divided into prophase, metaphase, anaphase, and telophase because prokaryotes have no nucleus and no centromeres. The ability of some multicellular animals, such as echinoderms and flatworms, to regenerate two whole organisms after having been cut in half, is also not the same as binary fission. Neither is vegetative reproduction of plants.

Process

Animation showing the complete process of binary fission.

Binary fission begins with DNA replication. 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.

After this replicational process, cell growth occurs.

Each circular DNA strand then attaches to the cell membrane. The cell elongates, causing the two chromosomes to separate.

Cell division in bacteria is controlled by the FtsZ, a collection of about a dozen proteins that collect around the site of division. 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. This 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.

Use by eukaryotic organelles

Eukaryotic organelles such as mitochondria, chloroplasts, and peroxisomes also reproduce within the eukaryotic cell by binary fission. How they are allotted to one descendant cell or the other during mitosis and cytokinesis is not yet clear.

References

  1. ^ Weiss, David S. (2004), "Bacterial cell division and the septal ring", Molecular Microbiology 54 (3): 588–597, doi:10.1111/j.1365-2958.2004.04283.x 

Simple English

Binary fission is a method of asexual reproduction. It is common in prokaryotes. A living cell divides into two cells. The two cells should be identical, but since mutation can occur, there might be slight differences. This process is basically when a prokaryotic organism divides into two parts (Each with a separate nucleus). the parent cell divides to give rise to two daughter cells, the daughter cells then each develop into individual parent cells and give rise to two more daughter cells EACH, and so on and so forth.









Got something to say? Make a comment.
Your name
Your email address
Message