ARS (Agricultural Research Scientist) Exam 2006

IARI, New Delhi

Subject: Biotechnology (Agricultural Sciences)

Paper II


  1. What is Molecular Markers? How do they differ from biochemical markers? Discuss their utility in plant Biotechnology with suitable examples.
  2. List all comparisons between the chloroplast genome and the nuclear genome. Describe the chloroplast transformation method and give its advantages over the nuclear transformation procedure in plants.
  3. Describe the basic step and mechanism of nitrogen fixation in legumes with special emphasis on the role of nif genes.
  4. What is RNAi? Describe the various mechanism of gene silencing and its significance in crop improvement.
  5. Give the detail account of the current status of transgenic crops at global level and critically view the importance of transgenics in Indian Agriculture.
  6. (a) How is double fertilization accomplished in plants? What is the fate of the egg and the endosperm nucleus?

(b) How does gamete formation in higher plants differ from that in higher animals?


(a) What is an enzyme and how does work?

(b) What are different methods of enzyme immobilization? Explain their industrial application with advantages.

  1. Distinguish between forward and reverse genetics, and explain how these approaches are useful tools for crop improvement.


What are different methods of gene isolation? Describe the essential steps involved in isolation of R genes how any plant species the map-based cloning method.

  1. What is the promoter? List various promoters with suitable examples in each case. Describe the currently available methods of isolation of plant promoters.


What is microarray technique? Give the principle on which it is based. What purpose is the technique widely used for? Describe the procedure in detail with a suitable example.

  1. What are QTLs? Explain how they are identified and used in crop improvement programmes.


What is a genetic linkage map? Describe the various steps involved in constructing a genetic linkage map in rice.

  1. What is photoremediation? How does it differ from other method of bioremediation? Explain in detail the mode of action of phytoremediation with suitable examples.


Describe the use of microbes for the production of : (a) Hydrogen, and (b) Hydrocarbons, as source of energy with associated advantages, if any.