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Interphase 1 Interphase Interphase 1 Interphase Interphase is the phase of the cell cycle in which the cell spends the majority of its time and performs the majority of its purposes including preparation for cell division. In preparation for cell division, it increases its size and makes a copy of its DNA. Interphase is also considered to be the 'living' phase of the cell, in which the cell obtains nutrients, grows, reads its DNA, and conducts other "normal" cell functions. The majority of eukaryotic cells spend most of their time in interphase. Interphase does not describe a cell that is merely resting but is rather an active preparation for cell division. A common misconception is that interphase is the first stage of mitosis. However, since mitosis is the division of the nucleus, prophase is actually the first stage.[1] An illustration of interphase in Gray's Anatomy. The chromatin has not yet In interphase, the cell gets itself ready for mitosis or meiosis. Somatic cells, condensed, and the cell is undergoing its normal functions. or normal diploid cells of the body, go through mitosis in order to reproduce themselves through cell division, whereas diploid germ cells (i.e., primary spermatocytes and primary oocytes) go through meiosis in order to create haploid gametes (i.e., sperm and ova) for the purpose of sexual reproduction. Identification Under a microscope, interphase can be recognized because the nuclear An image of the nucleus of a cell (HT1080) currently in interphase (probably G1). Note: membrane is still intact, the chromatin has not yet condensed, and Cytoplasm of this cell or the neighboring chromosomes are not visible, though the nucleolus may be visible as an cell is not visible (top-left), which is enlarged dark spot. The centrioles and spindle fibers are also not yet visible, currently in the telophase of mitosis. Image though the centrosome, which contains and organizes them, may be visible taken using an optical microscope and DAPI staining of DNA. near the nucleus. Stages of interphase There are three stages of interphase, with each phase ending when a cellular checkpoint checks the accuracy of the stage's completion before proceeding to the next. The stages of interphase are: • G (Growth 1), in which the cell grows and functions normally. During this time, much protein synthesis occurs 1 and the cell grows (to about double its original size) - more organelles are produced, increasing the volume of the cytoplasm. If the cell is not to divide again, it will remain in this phase. • Synthesis (S), in which the cell duplicates its DNA (via semiconservative replication). • G (Growth 2), in which the cell resumes its growth in preparation for mitosis. 2 • In addition, some cells that do not divide often or ever, enter a stage called G (Gap zero), which is either a stage 0 separate from interphase or an extended G phase, which follows the restriction point, a cell cycle checkpoint 1 found at the end of G . 1 The duration of time spent in interphase and in each stage of interphase is variable and depends on both the type of cell and the species of organism it belongs to. Most cells of adult mammals spend about 20 hours in interphase, this accounts for about 90% of the total time involved in cell division.[2] Interphase 2 Interphase within sequences of cellular processes Interphase and the cell cycle When G is completed, the cell enters a relatively brief period of nuclear and cellular division, composed of mitosis 2 and cytokinesis, respectively. After the successful completion of mitosis and cytokinesis, both resulting daughter cells re-enter G of interphase. 1 In the cell cycle, interphase is proceeded by telophase and cytokinesis of the M phase. In alternative fashion, interphase is sometimes interrupted by G phase, which, in some circumstances, may then end and be followed by 0 the remaining stages of interphase. After the successful completion of the G checkpoint, the final checkpoint in 2 interphase, the cell proceeds to prophase, or in plants to preprophase, which is the first stage of mitosis. G phase is viewed as either an extended G phase where the cell is neither dividing nor preparing to divide and or as 0 1 a distinct quiescent stage which occurs outside of the cell cycle.[3] Interphase and other cellular processes In gamete production interphase is succeeded by meiosis. In programmed cell death, interphase is followed or preempted by apoptosis. References [1] The Cell Cycle & Mitosis Tutorial (http:/ / www. biology. arizona. edu/ Cell_bio/ tutorials/ cell_cycle/ cells3. html) The Biology Project - Cell Biology. University of Arizona. [2] Mader, S. S. 2007. Biology 9th Ed. McGraw Hill Higher Education, Boston, MA, USA. ISBN 978-0-07-325839-3 [3] Re: Are the cells in the G0 (g zero) phase of mitosis really suspended? (http:/ / www. madsci. org/ posts/ archives/ nov99/ 942335648. Cb. r. html) Erin Cram, Grad student, Molecular and Cellular Biology, University of CA, Berkeley. 1999. MadScience Network. Question ID 942142089.Cb. Article Sources and Contributors 3 Article Sources and Contributors Interphase Source: http://en.wikipedia.org/w/index.php?oldid=394720768 Contributors: .killjoy, A999999, AP1787, AThing, Agathman, Alansohn, Alt-takes better, Angela, Animeronin, Arcadian, Artaxiad, Bendzh, Bettia, Biggal6, BlueDevil, Bobo192, Bomac, Bongwarrior, Btippett2, Calvin08, Capricorn42, Cdc, Clark89, Coolblue79, CopperKettle, Courcelles, D. Wu, DanielCD, Darth Panda, DavidJ710, Deicas, Doktor Drakken, Donato0, Download, Drphilharmonic, ESkog, Earthdirt, Enzo Aquarius, Erick.Antezana, Fannysyouraunt2, Fkeidjn, FreplySpang, Fusionmix, Gail, Gamersedge, Gilliam, Glane23, Gohomeatron, Gonzo fan2007, Grandfinale0708, Gurch, Icairns, Ivanintegra96, J.delanoy, Jag123, JamMan, JamesAM, Johnuniq, Justin00220, Jzhou2oo6, Jóna Þórunn, Kristen Eriksen, Kusb, LOL, Lambiam, Leoadec, Leptictidium, Lexor, MC10, Madhero88, Maedin, Manway, Master RDC, Meli0908, Michael Angelkovich, Michaelm 22, Natewest, Netkinetic, Neverquick, NuclearWarfare, OMG its averyxoxo, Pbradfield, Persian Poet Gal, Peter.C, Philip Trueman, Pikachuwashere, Pinethicket, Player 03, Rklawton, Rob.desbois, Robertbyrne, Rumping, Salome777, Sionus, Slysplace, Snowolf, Sooshi67, Stephenchou0722, Super-Magician, Tabletop, Thadius856, The Phoenix, The Thing That Should Not Be, anonymous edits 347 ,کشرز ,Tide rolls, Ukulele, Versus22, Vivio Testarossa, Voyagerfan5761, Will Pittenger, Woogee, Woozle, Wtyler, Yakeyglee, Yamamoto Ichiro, Zsinj Image Sources, Licenses and Contributors Image:Interphase.png Source: http://en.wikipedia.org/w/index.php?title=File:Interphase.png License: Public Domain Contributors: Asa Gray Image:Interphase_and_part_of_Telophase_of_HT1080.PNG Source: http://en.wikipedia.org/w/index.php?title=File:Interphase_and_part_of_Telophase_of_HT1080.PNG License: Public Domain Contributors: User:JamMan License Creative Commons Attribution-Share Alike 3.0 Unported http:/ / creativecommons. org/ licenses/ by-sa/ 3. 0/.
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