डीएनए
thumb|250px|diene diaauksiraibo nyooklik aml (aangrezi: Deoxyribo Nucleic acid or DNA) jivit koshikaoan ke gunasootroan mean pae jane vale tantunuma anu ko kahate haian. isaki sanrachana ghumavadar sidhi ki tarah hoti hai. diene mean anuvaanshik koot nibaddh rahata hai.
bhautik sanrachana
diene anu trivimiy hota hai aur do tantuoan se bana hota hai jo ki ek-doosare ke charoan or kuandalit hote haian. phraiankalin aur vilkins ne diene ke eks kiran vivartan ke adhyayan se yah darshaya hai ki diene dvikuandilat hota hai. 1953 mean jems vatasan v phaiansis krik ko diene ki sanrachana ki khoj karane ke liye nobel puraskar diya gaya. vatasan aur krik m aaudal ke anusar-
- diene anu do kuandaliyoan se nirmit hai, jisamean diene ke do tantu hote haian. donoan tantu pratisamaantar roop mean rahate haian, jisaka ashay yah hua ki ek tantu mean nyookliyotaid ka anukram 5’ se 3’ ki disha mean aur doosare tantu mean 3’ se 5’ ki disha mean hota hai. (3’ v 5’ ka ashay un karban paramanuoan se hai, jisase ph aausphet samooh ju de rahate haian.)
- kundali ka adhar sharkara ph aausphet se nirmit hota hai aur naitrojani ksharak sharkara se sahalagn hote haian.
- donoan tantuoan ke ksharak haidrojan bandhoan dvara ju de hote haian.
- shargapaf ke niyamanusar ksharak yugman ati vishisht hota hai. ek edenin pyoorin ksharak sadaiv thaimin-pirimidin ksharak ke sath yugmit hota hai. pyoorin ksharak gvanin-pirimidin ksharak, saitosin ke sath sanyukt hota hai. ksharak ke ye yugm poorak ksharak kahalate haian.
manav rang par prabhav
ab yah sabit ho chuka hai ki kisi ek vyakti ka diene 99.9 pratishat doosare vyakti jaisa hi hota hai, chahe ve donoan alag-alag jati ke hi kyoan n hoan. baqi 0.1 pratishat mean jo vividhata hai vahi ek vyakti ko doosare se alag karati hai. is tathy ke adhar par jiv-vijnani kahate haian ki aj ka manav afrika mean 2 lakh sal pahale rahane vale homo sepiyans ka vanshaj hai. yani ham sabake poorvaj afriki the. afrika bahut garm pradesh hai. soory ki parabaiangani kiranoan se bachane mean kala rang b di madad karata hai. tvacha ka rang mailenin namak ek rasayan se nirdharit hota hai. mailenin ki matra ke adhik hone se tvacha ka rang kala ho jata hai. kala rang folet namak vitamin bi ko bhi nasht hone se bachata hai. kali tvacha soory ki tez kiranoan ko bhitar jane se rokati hai, jisase vitamin di3 ka utpadan prabhavit hota hai, lekin jab manav thande pradeshoan ki or badha to vitamin di3 ki kami se usaki tvacha ka rang halka p dane laga. kuchh visheshajnoan ka manana hai ki terah hazar sal pahale tak yooropiy logoan ka rang gahara hua karata tha, vah dhire-dhire gore hue.
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tika tippani aur sandarbh
bahari k diyaan
sanbandhit lekh
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