Question

Describe Watson and Crick model of DNA.

Answer 1

James Watson and Francis crick in 19 53 proposed double helix structure of DNA . THEY were awarded for noble prize.

salient features

1. the two strands of DNA are hellically coiled. each turn of double helix contain ten pair nucleotides.
2. distance between two paired nucleotides is 3.4 A
3. A complete turn of double helix is 34 Armstrong.
4. the two chains of DNA are in antiparallel directon that is one chain 5'-3',and another one in 3'-5'.
5. adinine is always paired with thymine with two hydrogen bond.

Answer 2

In Watson and Crick's model, the two strands of the DNA double helix are held together by hydrogen bonds between nitrogenous bases on opposite strands. Each pair of bases lies flat, forming a "rung" on the ladder of the DNA molecule. Base pairs aren't made up of just any combination of bases.