gun sootr
gunasootr ya kromojom (Chromosome) sabhi vanaspatiyon va praaniyon ki koshikaaon mein paaye jaane vaale tantu roopi pind hote hain, jo ki sabhi aanuvaanshik gunon ko nirdhaarit va sanchaarit karte hain. pratyek prajaati mein gunasootron ki sankhya nishchit rahati hain. maanav koshika mein gunasootron ki sankhya 46 hoti hai jo 23 ke jode mein hote hai. iname se 22 gunasootr nar aur maada me samaan aur apne-apne jode ke samajaat hote hai. inhein sammilit roop se samajaat gunasootr (Autosomes) kehte hai. 23vein jode ke gunasootr stri aur puroosh mein samaan nahi hote jinhe vishmajaat gunasootr (heterosomes) kehte hai.
anukram
sanrachana
gunasootr ki sanrachana mein do padaarth visheshat: sanmilit rahate hain-
- (1) diaakseeribonyookleeik aml (Deoxryibonucleic acid) ya di N A (D N A), tatha
- (2) histon (Histone) naamak ek prakaar ka proteen.
di N A hi aanuvanshik (hereditary) padaarth hai. di A na A (D N A) anu ki sanrachana mein chaar kaarbanik samaakshaar sammilit hote hain : do pyoorin (purines), do pirimideen (pyrimidines), ek cheeni-diaakseeriboj (Deoxyribose) aur faasaforik aml (Phosphoric acid). pyoorin mein aidinin (Adenine) aur gvaanin (Guanine) hote hai aur pirimideen mein thaaimeen (Thymine) aur saaitosin (Cytosine). di N A (D N A) ke ek anu mein do sootr hote hain, jo ek doosare ke chaaron aur sarpil roop mein valayit (spirallyicoiiled) hote hai. pratyek di N A (D N A) sootr mein ek ke peechhe ek chaaron kaarbanik samaakshaar is kram se hote hain-thaaimeen, saaitosin, aidineen aur gvaanin, evam ve paraspar ek vishesh dhang se jude hote hain.
in chaar samaakshaaron aur unase sambandhit sharkara aur faasforik aml anu ka ek ekak tetraanyookleeotid (Tetranucleotide) hota hai aur kai sahastr tetraanyookleeotidon ka ek di N A (D N A) anu banta hai.
vibhinn praaniyon ke di N A ki vibhinnata ka kaaran hai - samaakshaaron ke anukram mein antar hona. di N A aur aisa hi ek doosra nyookleeik aml aar N A (R N A) kaarbanik samaakshaar ki upasthiti ke kaaran paraabaingani ko adhikaansh 2,600 engastraum ke kshetr mein antarleen (absorb) karte hain. isi aadhaar par di N A ka ek koshika sambandhi maatraatmak aagaman kiya jaata hai.
prakaar
praaniyon mein do vishesh prakaar ke keindrasootr paae jaate hain. ek to kuchh diptara insekta (Diptera, Insecta) mein dinbheeya laaragranthi (larval salivary gland) ke keindrakon mein paaya jaata hai. ye gunasootr usi jaati ke saadhaaran gunasootron ki apeksha kai sau gune lambe aur chaude hote hain. is kaaran inhein mahaagunasootr (Giant chromosomes) kehte hain. inki sanrachana saadhaaran samasootran aur ardhasootran keindrasootron se kuchh bhinn dikhaai padti hai. yahaaain ek gunasootr ke sthaan par ek anuprasth pankti aisi kanikaaon ki hoti hai jinmein abhiranjit hote ki yogyata adhik hoti hain. gunasootr ke ek chhor se doosare tak bahut si aisi anuprasth pankti ki sab kanikaaeain ek samaan hoti hain aur anya panktiyon ki kanikaaon mein visheshataaeain aur vibhinnataaeain hoti hai. in gunasootron ke adhik lambe hone ke kaaran yeh samjha jaata hai ki inka poorn roop se visrpileekaran (despiralisation) hota hai aur kadaachit proteen ka kuchh badhaav bhi hota hain.
adhik chaude hone ke kaaran yeh hai ki ek gunasootr apne samaan ek doosare keindrak-tr ka sanshleshan karta hai. saadhaaran avastha mein samasootran ke samay ye donon sootr ek doosare se pruthak ho jaate hain, parantu mahaagunasootr mein yeh naheen hota. donon sootr ek doosare se jude hi rah jaate hain. mahaagunasootr ki sankhya saadhaaran gunasootr ki sankhya ki aadhi hoti hai, kyonki pratyek sootr apne samaan doosare sootr se yugmit ho jaata hai. is ghatna ko daihik yugman (Somatic pairing) kehte hain.
jantuon mein vichitr prakaar ka ek aur bhi gunasootr paaya jaata hai. isak lainpabrash gunasootr (Lampbrush chromosome) kehte hain. ye gunasootr aise jantuon ke andon ke keindrakon mein paae jaate hain jinmein andapeet ki maatra adhik hoti hai, jaise machhali, ubhayachar, urag, paksheegan ityaadi. gunasootr saadhaaran diploteen-daayaakineesis (Diplotene-diakinesis) gunasootron ke samaan do do yugmit sootron ke bane hote hain. donon yugmit sootr kuchh sthaanon par ek doosare se jude hote hain aur shesh sthaanon par ek doosarein se door door rahate hain. in jodon ko kiyejma samjha jaata hai. pratyek sootr par, jiskon kromonima (Chromonema) kehte hain, sthaan sthaan par vibhinn parisaan ki kanikaaeain hoti hain jinko kromimiyrs (Chromomeres) kehte hain. pratyek kromomiyr se ek jodi ya adhik paarshvapaash (lateral loops) jude hue hote hai. paarshvapaash bhi kromonima ke sadrush sootr ka bana hota hai, parantu iske chaaron or ribonyooklio-proteen kanikaaeain ekatrit ho jaati hain jisse ye sootr mote dikhaai dete hain. kromomiyr bhi kromonima se santat hote hain. keindrakaaeain vishesh gunasootr par utpann hoti hain.
adhikaansh jantuon ki pratyek koshika mein gunasootron ke do ekaatm kulak hote hain. paripakva lingakoshikaaon (mature sex-cells) mein ek kulak rah jaata hai. aise praani aur koshikaaeain dvignit (diploid) kahi jaati hain, parantu kuchh praaniyon, visheshat: paudhon, mein do se adhik kulak gunasootron ke hote hain yeh bahugunit (polyploid) kahe jaate hain.
yadi kisi dvigunit praani ke keindrakasutr dugune ho jaae, jisse usaki koshikaaeain mein pratyek sootr chaar chaar hon jaise, (ka1 ka1 ka1 ka1; kha1 kha1 kha1 kha1, ga1 ga1 ga1 ga1 ityaadi) to aise praani ka aatopauliplauid (aateetetraaplauid) [autopolyploid (autotetraploid)] kehte hain. yadi kisi dvigunit sankar (deploid hybrid) ke gunasootr dugune ho jaae to aise praani ko ailopauliplauid (allopolyploid) kehte hain. yadi ek dvigunit praani ka, jiskekeindrakasutr ka1 ka1 kha1 kha1 ga1 ga1 ityaadi hain, kisi doosare praani se, jiske gunasootr ka2 ka2 kha2 kha2 ga2 ga2 ityaadi hain, sankaran kiya jaae to usaki santaan ke gunasootr ka1 ka2 kha1 kha2 ga1 ga2 ityaadi honge. ka1 ka2 kha1 kha2 ityaadi ek doosare se bhinn honge aur inmein saadhaaranat: yugman naheen hoga. yadi is praani ke gunasootr dugune ho jaae to unki koshikaaeain mein ka1 ka1 ka2 ka2; kha1 kha1kha2 kha2; ga1 ga1 ga2 ga2, ityaadi gunasootr honge. yeh ailopauliplauid (ailotetraaplauid) kaha jaaega. pauliplauid mein chaar se adhik kulak bhi ho sakte hain.
yeh spasht hai ki otopauliplauid mein jaaigoteen avastha mein chatu:sanyojak (quadrivalents) utpann ho jaayainge, kyonki pratyek prakaar ke chaar chaar gunasootr upasthit hain aur chaar sootron ke yugman se ek chatu:sanyojak banta hai. koshikaavibhaajan ke samay pratyek dhruv ko baraabar baraabar sankhya mein gunasootr naheen mileinge. praaya: aisa hota hai ki ek chatu:sanyojak ke tootane se kisi dhruv par teen sootr pahuainche aur uske sanmukh dhruv par ek hi sootr pahuainche. koshikaavibhaajan ke ant par bane hue santati koshikaaon (daughter cells) mein gunasootr ya to adhik sankhya mein honge ya kam mein aur aise asantulan ka parinaam yeh hota hai ki koshika mar jaati hai. isi kaaran ototetraaplauid bahut kam urvar hote hain. ototetraaplauid paudhe saadhaaran dvigunit paudhon se bahut bade hote hain tatha unke beej bhi bahut bade hote hain, jisse urvarata kam hone par bhi ye gruhasthi ke liye adhik laabhadaayak siddh ho sakte hain. thandhak pahuainchaakar, ya kuchh ailakelaayadon ke prabhaav se, paudhe aatopauliplaaid banaae ja sakte hain.
ailotetraaplauid mein dasha iske vipreet hoti hain. yadi donon aadim maataapita ke sootr ek doosare se poorn roop se vibhinn hon to ailopauliplaaid kriyaatmak roop se dvigunit hai aur poorn roop se urvar hoga. jaise, yadi kisi sankar mein ka1 ka2, kha1 kha2, ga1 ga2 se sootr sarvatha bhinn hon to aisa sankar bandhya hoga, parantu iske gunasootron ke dugune hone se yeh avastha badal jaayagi. aisi koshikaaon mein ka1 ka1 ka2 ka2, kha1 kha1 kha2 kha2, ga1 ga1 ga2 ga2 ityaadi sootr honge aur jin shaakhaaon mein aisi koshikaaeain hongi unapar fool lageinge, kyonki aisi koshikaaon mein maaiotik vibhaajan safal hoga, ka1 ka1 se yugmit hoga, kha1 kha1 se ityaadi.
vibhinn vanaspatiyon va jantuon mein gunasootron ki sankhya
dhatoora straamoniam (Datura stramonium) mein dvigunit avastha mein 12 jodi gunasootr hote hain aur ardhasootran ke samay dvisanyojak bante hain. iske otopauliplauid mein 12 chatushk (48) gunasootr hote hai aur ardhasootran ke samay 12 chatu:sanyojak bante hain. isi bhaaainti primyoola saaineinsis (Primula sinensis) se dvigunit paudhe mein 12 jodi gunasootr hote hain aur ototetraaplauid mein 48 sootr hote hain evam ardhasootran ke samay ismein 9 se 11 chatu:sanyojak aur 2 se 6 tak dvisanyojak bante hain. soleman laaikoparasikaun (Solanum lycopersicon) ke dvigunit mein 12 jodi gunasootr hote hain aur uske ototetraaplauid mein 12 chatushk (48) gunasootr. ye sab paudhe hain.
kreepis rubra (Crepis rubra) aura kreepis foetida (Crepis foctida) mein 5 jodi gunasootr hote hain. inke sootr ek doosare se bahut bhinn naheen hote aur inke sankaran se utpann sankar mein ardhasutran ke samay 5 dvisanyojak bante hain. iske ailopauliplauid mein 20 kein drakasootr hote hain aur ardhasootran mein 0 se 5 chatu:sanyojak bante hain aur 0 se 10 dvisanyojak. spasht hai ki ailotetraaplauid bahut urvar naheen hoga. primyoola floribanda (Primula floribunda) aur primyoola restisileta (Primula resticillata) donon mein hi 9 jodi gunasootr hote hain, jo ek doosare ke praaya: samaan hote hain. inke sankaran se jo sankar banaata hai uske prityooja kivensis kehte hain. ismein bhi 9 jodi gunasootr hote hain. ardhasootran ke samay mein yugman kriya safal hoti hai aur 9 dvisanyojak bante hain. sootron ke dvigun hone se jo ailopauliplaaid banta hai usamein 9 chatushk (36) sootr hote hain aur aise paudhe mein 12 se 18 tak dvisanyojak bante hain aur 0 se 3 tak chatu:sanyojak. spasht hai ki chatu:sanyojaakon ki sankhya bahut kam hai aur kabhi kabhi ek bhi chatu:sanyojak naheen banta.
mooli (Raphanus) aur karamakalla (Brassica) mein se pratyek mein 9 jodi gunasootr hote hain, jo ek doosare se poornat: bhinn hote hain. inke sankaran se utpann sankar raifaanas braisika (Raphanus-Brassica) mein bhi 9 jodi gunasootr hote hain; parantu ardhasootran mein ek hi dvisanyojak naheen banta, kyonki yugman ki kriya safal naheen hoti aur sabhi sootr ayugmit rah jaate hain jisse 12 ek-sanyojak bante hain. iske sootr dvigun se utpann ailotetraaplauid mein 12 jodi sootr hote hain aur ardhasootran mein 12 sanyojak bante hain, chatu:sanyojak ek bhi naheen. parinaam yeh hota hai ki raifaanas-braisika-ailaatetraaplauid bahut urvar hota hai, yadyapi raifaanas-braisika-dvigunit bandhya hota hai.
jantuon mein pauliplauidi bahut kam pai jaati hai par yeh anishekajanit (Parthenogenetic) jantuon mein bahudha pai jaati hai. paudhon mein bahut si nai jaatiyaaain pauliplauid ke kaaran utpann hui hongi. iska pramaan isse milta hai ki ainjiausparmon (Angiosperms) ki lagbhag aadhi jaatiyaaain aisi hai jinke paripakva yugmakon (Gametes) ke gunasootron ki sankhya kisi sambandhit jaati ke yugmakeeya gunasootr ki sankhya ki gunit hai. gehooain ki kai jaatiyaaain hain. in jaatiyon ki mool yugmakeeya keindrakasutr sankhya 7 hai. gunasootron ki sankhya gehooain ki jaatiyon mein 7 ki gunit 14,21,42 tatha 49 tak pai jaati hai. isi bhaaainti tanbaakoo ki bhinn bhinn jaatiyon mein gunasootron ki sankhya 12 athva 12 ki gunit 24 hoti hai. paudhon mein prayog dvaara bahut se pauliplauid banaae gaye hain, jinmein ekaatmak sootron ke do kulak hote hain. ye urvar hote hain.
ismein sandeh naheen ki koshikaadravya, keindrak ke niyantran mein kaaryasheel hota hai. anek prakaar ke koshikaasamooh anyaanya kaaryon ke sanchaalan mein lage rahate hain. udaaharanat: agnyaash (Pancreas) ki eksokraain (Excorine) koshikaaeain vishesh paachak kinvaj utpann karti hain. gud ki nalika ki koshikaaeain rudhir se yooriya nikaal leti hain aur yakrut ki koshikaaeain glookos ko glaaikojan mein parint karke ekamit kar leti hain. spasht hai ki kisi bhi praani ki pratyek koshika mein uske sab jeen (Gene) saadhaaranat: upasthit hote hain. isaliye bhinn bhinn prakaar ki koshikaaon ke vividh prakaar ke proteenon (jinki ve bani hai) ki utpatti mein kuchh upayukt jeen to sakriya rahe honge aur shesh sab nishkriya ho gaye honge or unki sakriyta ke sambandh mein bhi yahi baat hoti hogi.