--%>
Assignment Help - homework help

Structure of a DNA molecule

Elaborate the structure of a DNA molecule?

E

Expert

Verified

The molecule of a DNA is double-stranded. The molecule takes the shape of a double helix.
The DNA molecule has two complementary strands oriented in an anti-parallel fashion. All strand is made up of nucleotides. A nucleotide has a base (a purine or pyrimidine), a sugar (between the other two components) called deoxyribose, and a phosphate group. Nucleotides are connected to each other with phosphodiester bonds, creating a sugar-phosphate backbone to each strand.
Base of each nucleotide projects into an interior cavity of helix. Every base is opposite other base: adenine (a purine) is every time paired with the thymine (a pyrimidine), and the guanine (purine) with the cytosine (pyrimidine); this phenomenon is known as complementary base pairing.
Every nucleotide forms hydrogen bonds with its complementary base on another strand. Two hydrogen bonds form among adenine and thymine; three hydrogen bonds form between guanine and cytosine.

   Related Questions in Chemistry

  • Q : Problem on physical and thermodynamic

    The shells of marine organisms contain calcium carbonate CaCO3, largely in a crystalline form known as calcite. There is a second crystalline form of calcium carbonate known as aragonite. Physical and thermodynamic properties of calcite and aragonite at 298

    		•
  • Q : Molecular Symmetry Types The number of

    The number of molecular orbitals and molecular motions of each symmetry type can be deduced. Let us continue to use the C2v point group and the H2O molecule to illustrate how the procedure develop

    		•
  • Q : Colligative properties give atleast two

    give atleast two application of following colligative properties

    		•
  • Q : Raoults law Give me answer of this

    Give me answer of this question. Provide solution of this question. Which one of the following is the expression of Raoult's law: (a) P-P1/P = n/n+N (b) P1-P/P = N/ N+n (c)P-P2/P1= N/ N-n (d) P1-P/P2= N-n/N

    		•
  • Q : Modes of concentration Which of the

    Which of the given modes of expressing concentration is fully independent of temperature: (1) Molarity (2) Molality (3) Formality (4) Normality Choose the right answer from above.

    		•
  • Q : Chemical formula of detergent Describe

    Describe the chemical formula of detergent?

    		•
  • Q : Molarity of cane sugar solution 171 g

    171 g of cane sugar (C12H22O11)  is dissolved in one litre of water. Find the molarity of the solution: (i) 2.0 M (ii) 1.0 M (iii) 0.5 M (iv) 0.25 M Choose the right answer from above.

    		•
  • Q : Problem on decomposition reaction

    Nitrogen tetroxide (melting point: -11.2°C, normal boiling point 21.15°C) decomposes into nitrogen dioxide according to the following reaction: N2O4(g) ↔ 2 NO2(g)<

    		•
  • Q : Avogadro's hypothesis Law Principle

    Avogadro's hypothesis Law Principle- Berzelius, a chemist tried

    		•
  • Q : Molarity of Sulfuric acid Choose the

    Choose the right answer from following. What is the molarity of H2SO4 solution, that has a density 1.84 gm/cc at 35c and contains solute 98% by weight: (a) 4.18 M (b) 8.14 M (c)18.4 M (d)18 M

    		•