1.What are macromolecules? Give examples.
Macromolecules are large complex molecules that occur in colloidal state in intercellular fluid. They are formed by the polymerization of low molecular weight micromolecules.
Polysaccharides, proteins, and nucleic acids are common examples of macromolecules.
2. Illustrate a glycosidic, peptide and a phospho-diester bond.
(a)
Glycosidic bond is formed normally between carbon atoms, 1 and 4, of neighbouring monosaccharide units.
(b)
Peptide bond is a covalent bond that joins the two amino acids by – NH – CO linkage.
(c)
Phosphodiester bond is a strong covalent bond between phosphate and two sugar groups. Such bonds form the sugar phosphate backbone of nucleic acids.
3. What is meant by tertiary structure of proteins?
The helical polypeptide chain undergoes coiling and folding to form a complex three-dimensional shape referred to as tertiary structure of proteins. These coils and folds are arranged to hide the non-polar amino acid chains and to expose the polar side chains. The tertiary structure is held together by the weak bonds formed between various parts of the polypeptide chain.
4. Find and write down structures of 10 interesting small molecular weight biomolecules. Find if there is any industry which manufactures the compounds by isolation. Find out who are the buyers. a) | Molecule | Structure | 1. | Adenosine | | 2. | Thymidine | | 3. | Sucrose | | 4. | Maltose | | 5. | Lactose | | 6. | Ribose | | 7. | DNA | | 8. | RNA | | 9. | Glycerol | | 10. | Insulin | |
(b)
| Compound | Manufacturer | Buyer | 1. | Starch products | Kosha Impex (P) Ltd. | Research laboratories, educational institutes, and other industries, which use biomolecules as a precursor for making other products. | 2. | Liquid glucose | Marudhar apparels | | | 3. | Various enzymes such as amylase, protease, cellulase | Map (India) L | | |
5. Proteins have primary structure. If