15,624
edits
Changes
Jump to navigation
Jump to search
{{Construction Site}}
|date=2014-01-14
Add category.
In cell biology, '''mitosis''' is a part of the cell cycle when replicated chromosomes are separated into two new nuclei. Cell division gives rise to genetically identical cells in which the number of chromosomes is maintained.<ref>{{REFweb
|url=https://www.britannica.com/science/cell-biology/Cell-division-and-growth
|title=Cell division and growth |website=britannica.com
|publisher=ENCYCLOPÆDIA BRITANNICAEncyclopædia Britannica |accessdate=2019-10-10
}}</ref> In general, mitosis (division of the nucleus) is preceded by the S stage of interphase (during which the DNA is replicated) and is often accompanied or followed by cytokinesis, which divides the cytoplasm, organelles and cell membrane into two new cells containing roughly equal shares of these cellular components.<ref>{{REFweb
|last=Carter
|first=J. Stein
|title=Mitosis
|url= http://biology.clc.uc.edu/courses/bio104/mitosis.htm |website= biology.clc.uc.edu |url-status=live |archive-url=https://web.archive.org/web/2012102708411520151114201118/http://biology.clcwww.ucnature.educom/coursesscitable/bio104topicpage/mitosis.htm-and-cell-division-205 |website= |archive-date=2012-10-27 |accessdate=2019-10-10}}</ref> Mitosis and cytokinesis together define the '''mitotic''' ('''M''') '''phase''' of an animal cell cycle—the [[cell division|division]] of the mother cell into two daughter cells genetically identical to each other.
The process of mitosis is divided into stages corresponding to the completion of one set of activities and the start of the next. These stages are prophase, prometaphase, metaphase, anaphase, and telophase. During mitosis, the chromosomes, which have already duplicated, condense and attach to spindle fibers that pull one copy of each chromosome to opposite sides of the cell.<ref>{{REFweb
|url=http://www.nature.com/scitable/topicpage/mitosis-and-cell-division-205#
|website=www.nature.com
|access-date=2015-11-16 |url-status=live |archive-url=https://web.archive.org/web/20151114201118/http://www.nature.com/scitable/topicpage/mitosis-and-cell-division-205 |archive-dateaccessdate=20152019-1110-1410
}}</ref> The result is two genetically identical daughter nuclei. The rest of the cell may then continue to divide by cytokinesis to produce two daughter cells.<!--<REF name=Maton1997/>--> Producing three or more daughter cells instead of the normal two is a mitotic error called tripolar mitosis or multipolar mitosis (direct cell triplication / multiplication).<ref name="Occurrence 2014">{{REFjournal
|last=Kalatova |init=B, |last2=Jesenska |init2=R, |last3=Hlinka |init3=D, |last4=Dudas |init4=M
|title=Tripolar mitosis in human cells and embryos: occurrence, pathophysiology and medical implications
|url=https://www.researchgate.net/publication/270288317_Tripolar_mitosis_in_human_cells_and_embryos_Occurrence_pathophysiology_and_medical_implications
|journal=Acta Histochemica
|volume=117
|pubmedID=25554607
|DOI=10.1016/j.acthis.2014.11.009
|accessdate=2019-10-10
}}</ref> Other errors during mitosis can induce apoptosis (programmed cell death) or cause mutations. Certain types of cancer can arise from such mutations.<ref>{{REFjournal
|last=Kops |init=GJ, |last2=Weaver |init2=BA, |last3=Cleveland |init3=DW
|title=On the road to cancer: aneuploidy and the mitotic checkpoint
|journal=Nature Reviews. Cancer
|issue=10
|pages=773–785
|date=2005-10-01 |url=https://www.nature.com/articles/nrc1714
|pubmedID=16195750
|DOI=10.1038/nrc1714
|accessdate=2019-10-10
}}</ref>
==Mitosis and the foreskin==
Placing human tissue under tension causes the cells to sense the need for more tissue. The cells then start to divide and create more tissue identical to the original tissue. The additional tissue results in [[tissue expansion]], which is a recognized medical practice. Tissue may be placed under tension by applying traction, [[stretching]] [[skin]] manually, or by tugging with a device.
* Men who have a narrow tight [[foreskin]] or [[phimosis]] may stretch the narrow part of their foreskin laterally to cause mitosis, which results in a wider, retractable foreskin.
* Men who have been [[circumcision| circumcised]] may stretch their residual [[shaft skin]] longitudinally to lengthen it until it takes the shape of a foreskin.
* [[Intact]] men who wish to have a longer foreskin may stretch their foreskin longitudinally to make it longer.
{{SEEALSO}}
* [[Foreskin restoration]]
* [[Stretching]]
* [[Tissue expansion]]
{{LINKS}}
* {{REFweb
|url=https://www.eurostemcell.org/system/files/documents/resources/Introducing_SCs_slides_Jan2012.pdf
|archived=
|title=Introducing stem cells
|trans-title=
|language=
|last=
|first=
|author-link=
|publisher=Centre for Regenerative Medicine
|website=
|date=
|accessdate=2022-03-08
|format=PDF
|quote=
}}
* {{REFjournal
|last=Zollner
|first=Alexnader M.
|init=
|author-link=
|last2=Holland
|first2=Maria A.
|init2=
|author2-link=
|last3=Honda
|first3=Kord S.
|init3=
|author3-link=
|last4=Gosan
|first4=Arun K.
|init4=
|author4-link=
|last5=Kuhl
|first5=Ellen
|init5=
|author5-link=
|etal=no
|title=Growth on demand: Reviewing the mechanobiology of stretched skin
|trans-title=
|language=
|journal=J Mech Behav Biomed Mater
|location=
|date=2013-12
|volume=28
|issue=
|article=
|page=
|pages=
|url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3758413/
|archived=
|quote=
|pubmedID=23623569
|pubmedCID=3758413
|DOI=10.1016/j.jmbbm.2013.03.018
|accessdate=2022-03-08
}}
* {{REFjournal
|last=Razzak
|first=
|init=MA
|author-link=
|last2=Hossain
|first2=
|init2=MS
|author2-link=
|last3=Radzi
|first3=
|init3=ZB
|author3-link=
|etal=yes
|title=Cellular and Molecular Responses to Mechanical Expansion of Tissue
|trans-title=
|language=
|journal=Front. Physiol.
|location=
|date=2016-11-15
|volume=7
|issue=
|article=
|page=
|pages=540
|url=https://www.frontiersin.org/articles/10.3389/fphys.2016.00540/full
|archived=
|quote=
|pubmedID=27899897
|pubmedCID=5111402
|DOI=10.3389/fphys.2016.00540
|accessdate=2022-03-08
}}
{{REF}}
[[Category:Education]]
[[Category:Physiology]]
[[Category:Foreskin restoration]]