Prophase , from the ancient Greek before and stage , is a stage of mitosis in which the chromatin coils into double rod shaped structures called chromosomes in which the chromatin becomes visible. This process, called chromatin condensation , is mediated by the condensin complex. Since the genetic material has been replicated in the prior interphase of the cell cycle , there are two identical copies of each chromosome in the cell, called homologous chromosomes. Identical chromosomes, called sister chromatid s, are attached to each other at a DNA element present on every chromosome called the centromere . Also during prophase, giemsa staining can be applied to elicit G banding in chromosomes. Also, once the chromosomes form, the nucleolus fades. Prophase accounts for approximately 3 of the cell cycle s duration. An important organelle in mitosis is the centrosome , the microtubule organizing center in metazoans . During prophase, the two centrosomes, which replicate independently of mitosis, have their microtubule activity increased due to the recruitment of tubulin. The centrosomes will be pushed apart to opposite ends of the cell nucleus by the action of molecular motor s acting on the microtubules. Basically, the chromatin in the nucleus coils into chromosomes. The nucleolus disintegrates and the centrosomes move to opposite poles of the cell, forming a bridge of spindle fibers. In prometaphase , the next step of mitosis, the nuclear membrane falls apart and the chromosomes are captured by the microtubules. ref cite web title Biology of plants chapter Section 1. The Biology of the Plant Cell 3. The Plant Cell and the Cell Cycle pages 58 67 isbn 978 0 7167 1007 3 oclc 56051064 id LCCN 2004 053303 url http books.google.com ?id 8tz2aB1 jb4C&pg PA58 year 2005 ref References references External links http www.macroevolution.net prophase.html Prophase at http www.macroevolution.net ... Mitosis ca Profase cs Prof ze de Mitose Prophase es Profase fa fr Prophase hy io Profazo ... more details
PMAT may refer to Plasma membrane monoamine transporter PMAT Four of the phases of Mitosis Prophase, Metaphase, Anaphase, and Telophase. disambig ... more details
Refimprove date December 2009 Orphan date December 2009 A chromomere , also known as an idiomere , is one of the serially aligned beads or granules of an eukaryotic chromosome , resulting from local coiling of a continuous DNA thread. ref http www.highbeam.com doc 1P1 28729514.html Chromomere The Mosby Medical Encyclopedia ref It is visible on a chromosome during the prophase of meiosis and mitosis . Giant banded Polytene chromosome Polytene chromosomes resulting from the replication of the chromosomes and the synapsis of homologs without cell division is a process called endomitosis. These chromosomes consist of more than 1000 copies of the same chromatid that are aligned and produce alternating dark and light bands when stained. The dark bands are the chromomere. The chromomeres are present during leptotene phase of prophase I during meiosis. During zygotene phase of prophase I, the chromomeres of homologs align with each other to form homologous rough pairing homology searching . These chromomeres helps provide a unique identity for each homologous pairs. There are more than 2000 chromomeres on 20 chromosomes of maize. References Reflist External links http www.nature.com cr journal v12 n5 full 7290142a.html Preparation and analysis of spermatocyte meiotic pachytene bivalents of pigs for gene mapping Nature http www.nature.com hdy journal v81 n6 full 6884320a.html Physical mapping of DNA repetitive sequences to mitotic and meiotic chromosomes of Brassica oleracea var. alboglabra by fluorescence in situ hybridization Nature http www.springerlink.com content p7684u1ln87j6735 Chromonema and chromomere Springerlink Category Chromosomes Genetics stub ca Crom mer es Crom mero it Cromomero pt Crom meros ... more details
BimC is a subfamily of KRP s and its function is to separate the duplicated centrosomes during mitosis . Early in prophase , while the nuclear envelope is still intact, dynamic microtubules from each aster spindle overlap at their plus ends. KRPs of the bimC family self associate through their tails forming a bipolar motor like myosin II . These bipolar motors slide the oppositely oriented microtubule past each other, thereby pushing the spindle poles apart sliding of antiparallel microtubels . Category Proteins biochem stub ... more details
Unreferenced date January 2008 A bivalent , sometimes referred to as a tetrad , is a pair of associated homologous chromosome s held together by a complex after chromosome replication. During meiosis the Prophase I stage of Meiosis I , the process of synapsis occurs in which bivalents are formed. Each replicated chromosome is composed of two chromatid s. Bivalents are formed as two homologous chromosomes undergo recombination. Chromosome movement to accommodate recombination places homologous chromosomes close enough to each other for a protein complex synaptonemal complex , consisting of a protein ZIP1 ZYP1 depending on species , to hold them together. This protein s sequence is not well conserved, though its structure is very similar in all species globular domains on the N and C termini with a well defined core . In the atypical model species D. melanogaster and C. elegans recombination occurs secondarily to synapsis. Most species Human, Mouse, Arabidopsis, Maize, Yeast, Lily, and many others create bivalents as a result of DNA repair and recombination. Recombination produces chiasmata which hold chromosomes together after the synaptonemal complex dissolves. Prophase 1 substage Diplotene Category Chromosomes Category Cell cycle de Bivalent Meiose pl Biwalent genetics stub ... more details
dablink For specific versions of Shanghai Welkin Animation Development Co, ltd or Welkin Animation name Welkin Animation logofile logosize logoalt logo2 launch closed date picture format share share as of share source network owner slogan country CHINA broadcast area headquarters former names replaced names sister names Welkin Animation timeshift names web http welkin animation.com terr serv 1 terr chan 1 sat serv 1 sat chan 1 cable serv 1 cable chan 1 sat radio serv 1 sat radio chan 1 adsl serv 1 adsl chan 1 online serv 1 online chan 1 notability Companies date July 2009 Welkin Animation Development Co, Ltd is primarily engaged in prophase devising, intermediate and step phase producing all kinds of animation as well as completely working for all aspects of animation business. At the core of company, the prophase department is including literature creation and edit, characterisation and artistic scene design. Welkin Animation produces both tradition 2D animation as well as 3D CGI animation. Among their credits include Music Up Currently Welkin has co produced Galactik Football with Alphanim and Famille Fantomes with Carrere Group External links http welkin animation.com Category Animation studios ... more details
An aster is a cell biology cellular structure shaped like a star polygon star , formed around each centrosome during mitosis in an animal cell. ref Campell Biology , p.221 ref Astral rays, composed of microtubules , radiate from the centrosphere and look like a cloud. During mitosis, there are four stages of cell division Prophase , Metaphase , Anaphase , and Telophase . During prophase, two aster covered centrosomes migrate to opposite sides of the Cell nucleus nucleus in preparation of mitotic spindle formation. During metaphase, the astral rays connect to the lined up chromosomes at their centromere . Afterwards, during anaphase, the astral rays pull the chromosomes apart into its individual chromatids and pull them towards the centrosomes, located at opposite ends of the cell. This allows the cell to divide properly with each daughter cell containing full replicas of chromosomes. In some cells, the positions of the asters also determine the site of cell divisions. Notes reflist 2 References Citation last Campbell first Neil A, author link Neil Campbell scientist last2 Reece first2 Jane B. author2 link Jane Reece title Biology place San Francisco, CA publisher Benjamin Cummings year 2005 edition 7th isbn 0805371710 See also Astral microtubules Mitosis cell biology stub Category Cell biology Category Cell cycle Category Mitosis ... more details
Orphan date October 2010 The leptotene stage , also known as the leptonema , is the first of five substages of prophase I in meiosis . The term leptonema derives from Greek words meaning thin threads . ref name Snustad 2008 cite book title Principles of Genetics last1 Snustad first1 DP last2 Simmons first2 MJ year 2008 month December edition 5th isbn 9780470388259 publisher Wiley ref rp 27 A cell destined to become a gamete enters the leptotene stage after its chromosomes are DNA replication duplicated during interphase . During the leptotene stage those duplicated chromosomes each consisting of two sister chromatids condense from diffuse chromatin into long, thin strands that are more visible within the cell nucleus . The next stage of prophase I in meiosis is the zygotene stage. ref name Snustad 2008 rp 27 ref name Lewins Genes X cite book title Lewin s Genes X edition 10th last1 Krebs first1 JE last2 Goldstein first2 ES last3 Kilpatrick first3 ST isbn 9780763766320 publisher Jones & Barlett Learning year 2009 month November ref rp 353 References reflist Category Cellular processes ... more details
Image Preprophase.jpg 350px right thumb Microtubule dynamics during preprophase and prophase in plant cell mitosis, modified from Donukshe et al. ref name Dhonukshe cite journal author Dhonukshe, P, Mathur, J, H lskamp, M, Gadella, TWJ title Microtubule plus ends reveal essential links between intracellular polarization and localized modulation of endocytosis during division plane establishment in plant cells journal BMC Biology date 2005 volume 3 pages 11 doi 10.1186 1741 7007 3 11 pmid 15831100 pmc 1087477 ref The images follow a Tobacco BY 2 cells tobacco BY 2 cell through the first stages of mitosis c. 12 minutes . The growing ends of microtubules are shown in green labeled with green fluorescent protein fused to the microtubule plus end binding protein EB1 of Arabidopsis thaliana . N Nucleus, V Vacuole, PPB Preprophase band, MTN Microtubule nucleation starts at the nuclear envelope, NEB Nuclear envelope breakdown at the onset of prometaphase . Also see the http www.biomedcentral.com 1741 7007 3 11 suppl S5 movie corresponding to this figure. Preprophase is an additional phase during ... . It precedes prophase and is characterized by two distinct events The formation of the preprophase ... the precise location of the division plane and future cell wall before the cell enters prophase . This is achieved ... site for the cell plate . It consists of microtubules and microfilament s actin and persists into prophase. Spindle formation occurs during prophase with the axis perpendicular to the plane surrounded ... kinetochore mediated spindle assembly after the nuclear envelope breaks down at the end of prophase ... 22 AID CM3 3.0.CO 2 H issue 1 ref Transition into prophase During progression from preprophase into prophase ... axis. This structure is called the prophase spindle . Triggered by nuclear envelope breakdown at the end of prophase, the preprophase band disappears ref name Dixit cite journal author Dixit ... 11926062 doi 10.1007 s007090200012 issue 1 2 ref and the prophase spindle matures into the metaphase ... more details
wiktionary tetrad Tetrad may refer to Meiosis Meiosis I Tetrad chromosomal pairing , Bivalents or Tetrad of homologous chromosomes consisting of four synapsed chromatids that become visible during the Pachytene stage of meiotic prophase Sporogenesis Formation of reproductive spores Tetrad pollen formation , group of four haploid and immature pollen grains in tetrahedral fashion produced by meiotic microsporogenesis Tetrad genetics , the four spores of a yeast Tetrad general relativity , a mathematical frame of reference in general relativity Tetractys or Tetrad , Greek philosophy Tetrad index notation , a concept in differential geometry Tetrad music , a set of four notes Tetrad unit of area , an area 2km x 2km square Tetromino , a shape composed of four squares Tetrad of media effects , a pedagogical tool disambig ... more details
wiktionarypar dyad Dyad may refer to Dyad biology , a pair of sister chromatids occurring in prophase I of meiosis may also be used to describe protein morphology Dyad Greek philosophy , Greek philosophers principle of twoness or otherness Dyad music , a set of two notes or pitches Dyad sociology , mostly refers to pairs of individuals such as couples, co authors, twins, partners in crime, etc. Dyad pedagogy , in education Dyad, in engineering kinematics , a linkage in a planar mechanism that has two possible assembly modes Dyad, in obstetrics , the pregnant mother and fetus Dyadic tensor , in mathematics See also Dyadic disambiguation Diad Dryad disambig de Dyade nl Dyade sr ... more details
Unreferenced auto yes date December 2009 Interkinesis is a period of rest that cell biology cells enter during meiosis . ref http www.macroevolution.net interkinesis.html Interkinesis http www.macroevolution.net biology dictionary.html Online biology dictionary . 2012 ref It is an intermediate stage that occurs between meiosis I and II. No DNA replication occurs during any stage of meiosis. Many plants skip telophase I and interkinesis, going immediately into prophase II. Each chromosome still consists of two chromatid s. References references External links http www.macroevolution.net interkinesis.html Interkinesis at http www.macroevolution.net biology dictionary.html Online Biology Dictionary Category Cellular processes Genetics stub pl Interkineza ... more details
unreferenced date June 2009 Telophase pronounced tee low faze or tell uh faze from the ancient Greek end and stage , is a stage in both meiosis and mitosis in a eukaryote eukaryotic cell biology cell . During telophase, the effects of prophase and prometaphase the nuclear membrane and nucleolus disintegrating are reversed. Two daughter Cell nucleus nuclei form in the cell. The nuclear envelopes of the daughter cells are formed from the fragments of the nuclear envelope of the parent cell. As the nuclear membrane forms around each pair of chromatid s, the nucleoli reappear. The chromosomes also unwind back into the chromatin they are supposed to be. Telophase accounts for approximately 2 of the cell cycle s duration. Image TelophaseIF.jpg thumb Reappearance of the nuclear membrane and nucleolus the Telophase Cytokinesis usually occurs at the same time that the nuclear envelope is reforming, yet they are distinct processes. In plant cells, vesicles derived from the Golgi apparatus move to the middle of the cell along a microtubule scaffold called the phragmoplast . This structure directs packets of cell wall materials which coalesce into a disk shaped structure called a cell plate . The cell plate grows out centrifugally and eventually develops into a proper cell wall, separating the two nuclei. Once this is finished, mitosis is complete, and Cytokinesis begins. External links wiktionary http www.macroevolution.net telophase.html Telophase at http www.macroevolution.net telophase.html Online Biology Dictionary commonscat inline Navbox name Cell cycle title Cell cycle group1 Interphase list1 G1 phase S phase G2 phase group2 Cell division M phase list2 Mitosis Prophase , Prometaphase , Metaphase , Anaphase , Telophase Cytokinesis group3 Cell cycle checkpoint s list3 Restriction point Postreplication checkpoint group4 list4 group5 list5 cell biology stub bg ca Telofase de Mitose Telophase fa fr T lophase hy ht Telofaz no Telofase p ... more details
Pfam box Symbol RPA C Name Replication protein A C terminal Pfam PF08784 InterPro IPR014892 PROSITE PDB PDB 1dpu Replication protein A RPA is a protein that binds single stranded DNA in eukaryotic cells. ref cite journal title Replication protein A heterotrimeric, single stranded DNA binding protein required for eukaryotic DNA metabolism last Wold first MS journal Annual Review of Biochemistry year 1997 volume 66 issue 1 pages 61 92 doi 10.1146 annurev.biochem.66.1.61 pmid 9242902 ref During DNA replication , RPA prevents single stranded DNA ssDNA from winding back on itself or from forming secondary structures. This keeps DNA unwound for the polymerase to replicate it. RPA also binds to ssDNA during the initial phase of homologous recombination , an important process in DNA repair and Meiosis Prophase I prophase I of meiosis . Like its role in DNA replication, this keeps ssDNA from binding to itself self complementizing so that the resulting nucleoprotein filament can then bound by RAD51 Rad51 and its cofactors. ref cite journal title Homologous recombination in DNA repair and DNA damage tolerance last1 Xuan first1 L last2 Wolf Dietrich first2 H journal Cell Research year 2008 volume 18 issue 99 pages 99 113 doi 10.1038 cr.2008.1 pmid 18166982 ref A bacterial homolog is called single strand binding protein SSB . References reflist Category Genetics genetics stub DNA replication DNA repair es Prote na de replicaci n A fr Prot ine de R plication A ru ... more details
about parapsychology parapsychological uses such as Psionics psionic abilities Psychokinesis fiction al uses, such as pyrokinesis List of comic book superpowers Unreferenced date August 2009 wiktionary kinesis kinesis , from Greek language Greek , movement, motion , is a Affix suffix that denotes movement. The word Kinesis itself similarly indicates movement, particularly in biology. Cytokinesis The step of cell division following telophase of mitosis , when the cytoplasm is divided into two of roughly equal proportion to the two new daughter cell biology cells . This ensures there will be enough organelle s for each of the new cells. wiktionary diakinesis Diakinesis The last stage of prophase , in which the nucleolus and nuclear envelope disappear, spindle fibers form, and the chromosome s shorten in preparation for anaphase . Interkinesis A pause between two phases of meiosis . Karyokinesis Refers specifically to the division and replication of the cell nucleus nucleus . Photokinesis A movement made in response to enabled by the presence of light See also Phototaxis DEFAULTSORT Kinesis Category Greek suffixes vocab stub lang stub de kinese es Quinesis Medicina uk ... more details
About the DJs Dave and Brenden Webster the Caetano Veloso album Transa album Refimprove date February 2011 Transa is a United Kingdom British Electronic dance music EDM production Disc jockey DJ unit, composed of the brothers Dave and Brenden Webster. They have produced mostly trance music over their career, but have slipped into the realm of progressive house on occasion. Several of their songs and remix es have appeared on mix album s over the years, most notably Paul Oakenfold s first album in the Tranceport series and X Cabs s Exposure 1 . They have remixed for Brian Transeau BT , Art of Trance , Ti sto , Ferry Corsten , Venga Boys , Armin Van Burren, Blue Amazon and Alice Deejay . They have also recorded under the aliases Cascade and Catcher. Chart discography Prophase 1997 UK Singles Chart UK 65 Enervate 1998 UK 42 ref name British Hit Singles & Albums cite book first David last Roberts year 2006 title British Hit Singles & Albums edition 19th publisher Guinness World Records Limited location London isbn 1 904994 10 5 page 564 ref References Reflist External links http www.discogs.com artist Transa Transa at Discogs Category British electronic music groups Category Remixers Category Musical duos ... more details
Unreferenced date January 2007 orphan date November 2009 Infobox Album See Wikipedia WikiProject Albums Name Cream Anthems 97 Type Remix Album Artist Paul Oakenfold Cover Released November 10, 1997 Genre Electronic Dance Label Bmg Int l Cream Anthems 97 is a mix album , Disc 1 by Nick Warren and Disc 2 by Paul Oakenfold . Disc 1 Free Freestyle Orchestra Horizonti, Belo Original Mix Gunman Ajare Original Mix Breathe Nine Ways Original Mix Cowgirl Your Face In the Mirror Don t Be Afraid Brittany Remix Off Shore Disco Citizens Remix Everytime Nalin & Kane Mix Get Up Go Insane Rock N Roll Mix Sunchyme Block Rockin Beats Disc 2 Mystery Land Plastic Dreams Dave Morales Club Mix Remember Album Version Home Salt Tank Reconstruction Rendezvous Quadrophonic Mix Reflect Original Mix Cafe del Mar Three N One Mix Nightmare Original Sinister Strings Mix You re Not Alone Oakenfold Osborne Remix Flash Club Mix Y How Deep Is Your Love Original Mix X Ray Follow Me The Prophet Original Mix Schoenberg Original Marmion Mix Prophase X Cabs Remix One Category Paul Oakenfold remix albums Category 1997 remix albums Category Double remix albums 1990s electronic album stub ... more details
Premature chromosome condensation PCC occurs in eukaryote eukaryotic organisms when mitosis mitotic cell biology cells fuse with interphase cells. ref name springerlink Chromatin , a substance that contains genetic material such as DNA , is normally found in a loose bundle inside a cell s nucleus. During the prophase of mitosis, the chromatin in a cell compacts to form condensed chromosome s this condensation is required in order for the cell to divide properly. While miotic cells have condensed chromosomes, interphase cells do not. PCC results when an interphase cell fuses with a miotic cell, causing the interphase cell to produce condensed chromosomes prematurely. The appearance of a prematurely condensed chromosome depends on the stage that the interphase cell was in. ref name springerlink Chromosomes that are condensed during the G1 phase G sub 1 sub phase are usually long and have a single strand, while chromosomes condensed during the S phase appear crushed. Condensation during the G2 phase G sub 2 sub phase yields long chromosomes with two chromatid s. References reflist refs ref name springerlink cite journal url http www.springerlink.com content p930t72027618m44 journal Human Genetics accessdate 13 March 2010 year 1974 month December title The phenomenon of premature chromosome condensation its relevance to basic and applied research volume 32 issue 4 ref Category Chromosomes Category Mitosis cell biology stub ... more details
Unreferenced date May 2009 Deleted image removed Image Prometaphase flourescent.jpg thumb 160px In early prometaphase, the nuclear membrane has just degraded, allowing the microtubule s to quickly interact with the kinetochores on the chromosomes, which have just condensed. File Prometaphase 1.jpg thumb 160px The nuclear membrane dissolves as the microtubules invade the nuclear space. File PLoSBiol3.5.Fig1bNucleus46Chromosomes.jpg thumb 200px The 23 human chromosome territories during prometaphase in fibroblast cells. Deleted image removed Image Prometaphase flourescent2.jpg thumb 160px In late prometaphase, most of the chromosomes have begun the events of metaphase while the rest should have at least have one kinetochore connected. Prometaphase is the phase of mitosis following prophase and preceding metaphase , in eukaryote eukaryotic somatic Cell biology cell s. Prometaphase is sometimes simply included as a part of the prophase. In Prometaphase, the nuclear membrane disintegrates. Microtubules emerging from the centrosomes at the poles ends of the spindle reach the chromosomes, now highly condensed. At the centromere region, each sister chromatid has a protein structure called a kinetochore. Some of the spindle microtubules attach to the kinetochores, throwing the chromosomes into agitated motion. Other spindle microtubules make contact with microtubules coming from opposite pole. Forces exerted by protein motors associated with spindle microtubules move the chromosomes toward the center of the cell. Open and closed mitosis In open mitosis , microtubule s which have radiated from the two centrosome s located at the opposite poles of the cells invade the nuclear space as the nuclear membrane disassembles. This allows the microtubule s to reach for the chromosome s and attach to their kinecticores. Most fungi and many protist s, such as algae , undergo a variation called closed mitosis where the microtubules are able to penetrate an intact nuclear envelope through ... more details
stage of the first meiotic prophase, both in males and in females during gametogenesis. Previous ... prophase of meiosis I. References Moses MJ, Annu. Rev. Genet. 2 363 412 1968. Zickler D., Kleckner ... more details
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