Draw a labelled diagrams of
DWA helix
Answers
DNA has a double-stranded helical structure.
It was given by Watson and Crick model.
It is also known as B form of DNA.
It is made up of nitrogenous base, deoxyribose sugar, and phosphate.
The nitrogenous base, deoxyribose sugar, and phosphate link together forms the nucleotide chain.
The two nucleotide chain is arranged as stacks connected by phosphate.
The phosphate connects the 3' carbon atom of one sugar molecule and the 5' carbon atom of another deoxyribose sugar of next nucleotide chain by phosphodiester bonds.
3'-5' linkage by phosphodiester bonds makes the two strands as antiparallel strands.
Nitrogenous base is of two types purines and pyrimidines.
Adenine and guanine is purines, while thymine and cytosine is pyrimidines.
Purines are linked to pyrimidines by hydrogen bonds.
The adenine and thymine is linked by two hydrogen bonds while cytosine and guanine is linked by three hydrogen bonds.
The nitrogenous bases are linked to the sugar by N-glycosidic bonds.
It has a diameter of 20 A
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.
The total helix runs to a length of 34A
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.
The axial rise per base pair is 3.4 A
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Base pair per turn is 10A
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