1. Tardigrade
  2. Question
  3. Biology
  4. In a double stranded DNA, the sequence of nucleotides in one strand is 3'ATTCGCTAT5'. What will be the complementary sequence on the other strand?

Q. In a double stranded DNA, the sequence of nucleotides in one strand is What will be the complementary sequence on the other strand?

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Solution:

The Watson and Crick model of DNA has the following characteristic features:
  1. There are two strands, they run anti-parallel, which means, the orientation of the strands are opposite
  2. There are nucleotides, attached by the phsophodiester bonds which makes the backbone of dsDNA
  3. There are nitrogen-containing, heterocyclic bases.
  4. Bases are of two types, purines and pyrimidines.
  5. Bases are paired in two strands, and the pairing is called complementary, which indicates that purine is always paired with pyrimidine, and vice versa.
  6. The numbers of purines are always equal to numbers of pyrimidines.
  7. There are 10 base pairs in every turn of dsDNA, and the DNA is right-handed coiled structure.
  8. The distance between two bases are 0.34 nm and the distance of one complete turn is 3.4 nm.
  9. There are huge numbers of H-bonds, formed between the bases, which holds the two strands. When A pairs with T, there are 2 H-bonds, and when C pairs with G, there are 3 H-bonds.
Thus, considering the complementary base pairing nature, we can understand that,