Elementary plant Biochemistry and Biotechnology (2+1)

Macromolecular Structures: DNA

• In general, a single cell contains ~ 104 – 105 different kinds of molecules. Roughly half of these molecules are small, whose molecular weights usually do not exceed several hundred (E.g. inorganic ions and organic compounds).
  
• The others are polymers that are so massive (molecular weights from 104 – 1012 Da) and are called as macromolecules. These molecules are of three classes: proteins, nucleic acids and polysaccharides, which are polymers of amino acids, nucleotides and sugars, respectively.
• There are also subclasses of these groups. E.g. glycoproteins (proteins carrying sugar groups), lipoproteins (proteins carrying lipids or fats), lipopolysaccharides etc. Knowledge of the properties of macromolecules is essential for understanding living process.
  
• In this lecture, the structure of nucleic acid will be studied in details because it is the molecule of live, which store and carry information of live which is the primary function of nucleic acid