BIOCHEMISTRY Question Papers (Supple, Nov, 2008)

SET: 1

1. In what forms carbohydrates are stored in plants and animals. Give the structural formulae for the constituents concerned. Write short notes on it.

2. How the glucose level of blood is maintained in animals? Discuss the role of hormones in sugar regulation in the animal body.

3. Differentiate between aerobic and anaerobic hydrogen transfer. Compare the energy yield of the two processes.

4. Summarize the proper balance between the activities of the autotrophs and heterotrophs in our biosphere.

5. (a) How microorganisms use ATP and a powerful reductant to convert molecular nitrogen into ammonia? (b) How is ammonia assimilated into aminoacids?

6. (a) Define the term lipid. How are they extracted from a natural source? What are their general characteristic features? (b) What are storage lipids? What is their composition? Sketch their physiological functions.

7. List out some of the products obtained from microbial fermentations. What is the importance of industrial fermentations over the chemical synthesis that are carried out in laboratories?

8. What is non cyclic photophosphorylation? When this event takes place. Illustrate the electron flow with the help of a flow-sheer diagram.

SET: 2

1. What do you mean by carbohydrates? Discuss the carbohydrates that are membrane components.

2. How the glucose level of blood is maintained in animals? Discuss the role of hormones in sugar regulation in the animal body.

3. Summarize the sequence of reactions involved in malate aspartate shuttle.

4. Describe proteins conformation is stabilized largely by weak interaction.

5. List out the amino acids that are synthesized using the precursor alpha-ketoglutarate and sketch their biosynthesis.

6. (a) What are structural lipids? Give their structural characteristics. (b) which are the phospholipids that have ether-linked fatty acids. Give their structures and mention their physiological significance.

7. (a) What is substrate level posphorylation? Explain its significance. Illlustrate two reactions in which such phosphorylation reaction occur. (b) Sketch the biogenesis of ethanol

8. What is the electron flow in cyclic phosphorylation. When this occurs? Illustrate this phenomenon with the help of a flow sheet diagram.

SET: 3

1. Explain starch and glycogen are stored fuels?

2. How the glucose level of blood is maintained in animals? Discuss the role of Hormones in sugar regulation in the animal body.

3. How is a concentration gradient of proton transformed into ATP?

4. Summarize the sequence of process involved in nitrification.

5. What is a nitrogen cycle? Sketch the basic events involved in it. What are the enzymes involved in this cycle?

6. How a molecule of palmitic acid is completely oxidized in a mitochondrion. Enumerate the enzyme catalyzed reactions and calculate the energy yield?

7. Enumerate the different stages involved in the extraction of energy from food stuffs. Outline the major pathways involved in this process.

8. (a) Compare the basic structural features of chloroplasts and mitochondria. (b) How does photosynthesis in green and purple bacteria differ.

SET: 4

1. Write a short notes:
(a) Homopolysaccarides
(b) Heteropolysaccarides
(c) Formation of maltose
(d) Some common disaccarides

2. Explain the relationship between glyoxylate and citric acid cycle.

3. What do you understand by 'redox' reaction? Write a note on oxidation versus reduction in the biological system.

4. Describe the amino acid residues in proteins are L-stereo isomers.

5. What is the key intermediate in the synthesis of aromatic aminoacids? Sketch the biosynthesis of tryptophan from chorismate, how it is regulated?

6. (a) What are ceramides and sphingolipids? Give their structural features and mention their biological roles. (b) What are glycosphingolipids and cerebrosides. Mention their structural features.

7. Enumerate the different stages involved in the extraction of energy from food stuffs. Outline the major pathways involved in this process.

8. What is the mechanism of trapping the solar energy? What are the primary and secondary photoreceptor molecules? Explain the structural characteristics of chlorophylls.