Cleavage furrow

Cleavage furrow
In this electron micrograph of a cell, the cleavage furrow has nearly completely divided the cell.
Cilliate undergoing the last processes of binary fission, the cleavage furrow being clearly visible

In cell biology, the cleavage furrow is the indentation that begins the process of cleavage, by which animal and some algal cells undergo cytokinesis. The same proteins responsible for muscle contraction, actin and myosin begin the process of forming the cleavage furrow. This can only happen in animal cells. Plant cells do not form a cleavage furrow. Instead, plant cells begin cytokinesis with the formation of a cell plate. The cleavage furrow begins on the outside of the cell and moves inward towards the center while the cell plate begins in the center and grows outward to meet the cell wall. Furrow appears because a ring of actin filament forms just inside the plasma membrane, in a plane that bisects the cell. Myosin binds to these actin filaments. Myosin moves the ring of actin filaments on the side of the plasma membrane, and the ring shrinks in size and tightens. The shrinking ring pulls the membrane with it because it is attached to the plasma membrane. The actin and myosin filaments continue to slide past each other, tightening the ring further, until the original membrane is pinched in two and cell division is complete.



Wikimedia Foundation. 2010.

Игры ⚽ Поможем решить контрольную работу

Look at other dictionaries:

  • cleavage furrow — a deepening constriction of the plasma membrane at the equator of a dividing cell, formed by the pinching in of the membrane as the diameter of the contractile ring decreases …   Medical dictionary

  • Cleavage — may refer to: Cleavage (breasts), partial exposure of the separation between a woman s breasts. Cleavage enhancement, methods of making a person s breast cleavage look more substantial than it really is. Buttock cleavage, minor exposure of the… …   Wikipedia

  • Cleavage (embryo) — In embryology, cleavage is the division of cells in the early embryo. The zygotes of many species undergo rapid cell cycles with no significant growth, producing a cluster of cells the same size as the original zygote. The different cells derived …   Wikipedia

  • cleavage — 1. Series of mitotic cell divisions occurring in the ovum immediately following its fertilization. SYN: segmentation (2). SEE ALSO: c. division. 2. Splitting of a complex molecule into two or more simpler molecules. SYN: scission (2). 3 …   Medical dictionary

  • Cytokinesis — A cell that has almost completed cytokinesis. An arrow points to a centrosome that can still be seen …   Wikipedia

  • Mitosis — Not to be confused with meiosis, miosis, or myositis. Mitosis divides the chromosomes …   Wikipedia

  • Katsuma Dan — nihongo|Katsuma Dan|團 勝磨|Dan Katsuma|October 16, 1905 May 18, 1996 was a Japanese embryologist and cell biologist. He was born in 1905, the youngest son of Baron Dan Takuma, president of the Mitsui Gomei Kaisha Corporation. Takuma Dan was… …   Wikipedia

  • Glial fibrillary acidic protein — (GFAP) is an intermediate filament (IF) protein that is found in glial cells such as astrocytes, but also in other cell types such as Leydig cells in the testis and stellate cells in the liver.cite journal | author = J A Holash, S I Harik, G… …   Wikipedia

  • Phycoplast — The phycoplast is a microtubule structure observed during cytokinesis in members of the Chlorophyceae , the largest class of green algae.Cytokinesis in green algae occurs via a diverse range of mechanisms, including cleavage furrows in some algae …   Wikipedia

  • INCENP — Inner centromere protein antigens 135/155kDa, also known as INCENP, is a human gene.cite web | title = Entrez Gene: INCENP inner centromere protein antigens 135/155kDa| url = http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene Cmd=ShowDetailView… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”