Question

5 reasons that DNA is the stable genetic material

Answer 1

(a) DNA is more stable as it lacks the highly reactive 2'-OH species and it has thymine which is more stable than uracil found in RNA.

(b)The terms used in genetic code means  

Unambiguous means that each codon codes for only one amino acid.

Degenerate means that one amino acid can be coded by mopre than one codon.

Universal means that a given codon in DNA and mRNA specifies the same amino acid in all organisms from viruses, bacteria to human beings.

Answer 2

The Structural Stability of the DNA Double Helix

By John Brennan; Updated April 25, 2017



Under the conditions found in cells, DNA adopts a double helix structure. Although several variations on this double helix structure exist, all of them have the same basic twisted-ladder shape. This structurne gives DNA physical and chemical properties that make it very stable. This stability is important because it prevents the two DNA strands from breaking apart spontaneously and plays an important role in the way DNA is copied.




When two strands of DNA come together, they form weak chemical bonds called hydrogen bonds between the nucleotides in the two chains. Bond formation releases energy and thus contributes to a net increase in entropy. An additional entropy boost comes from interactions between the nucleotides in the center of the helix; these are called base-stacking interactions. The negatively-charged phosphate groups in the backbone of the DNA strands repel each other. However, this destabilizing interaction is overcome by the favorable hydrogen bonding and base-stacking interactions. This is why the double-helix structure is more stable than single strands: its formation causes a net gain in entropy.