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struktura e ADN:zinxhiret e ADN dhe lidhjet mes tyre

Cod. A26012005

ADN dhe ARN jane nje sekuence nukleotidesh qe jane te lidhur me njeri tjetrin.Ndryshimi qendron ne faktin se ne pergjithsi ADN eshte i perbere nga 2 zinxhire kurse ARN nga nje po nuk eshte e thene qe kjo te jete e vertete gjithmone. Cdo nukleotid lidhet me tjetrin me ane te lidhjeve fosfodiestere dhe me ane te lidhjeve hidrogjenore. Jane dy lidhje hidrogjenore ndermjet adenines dhe timines dhe 3 lidhje ndermjet guaines dhe citozines. Keto lidhje mund te duken lidhje te dobeta po mund te kujtoj se jane keto lidhje qe e mbajne ujin ne gjendje te lenget dhe ne baze te llogaritjeve te bera nese nuk do te egzistonin keto lidhje uji do te ishte ne gjendje te avullt qe ne temperaturen -81 grade celcius(informacion i marre nga libri i biologjise molekulare i wolf-it). Nukleotidet sic thashe ne formen e vecuar jane me 3 grupe fosfat por kur bashkohen i humbin 2 grupe per te dhene ate lidhje te qendrueshme.
Ne figuren me poshte do tu kerkoja te vinit re disa gjera: e para qe 2 zinxhiret e ADN jane ne drejtim te kundert njeri me tjetrin....

the DNA structure: DNA chains and the ligands between them
DNA and RNA are a sequence of nucleotides that are bound together. The difference between these to is that DNA is composed of 2 chains(formin a helix) while RNA usually is formed by one chain even why this is not always true becouse there are some exceptions. Every nucleotide is bound with the other through a phosphodiester link(in the same chain) and hydrogen links(between different chains). There are 2 hydrogen links between adenine and thymine and 3 between guanine and cytosine. These hydrogen links might seem weak links but imagine the fact that water would have been vapor at -81 degree if they were not present.the nucleotides are contain 3 phosphate groups and as they bind each other,they lose 2 of them to give a stable link.
In the figure below try to focus on a particular :the chains are antiparallel...