IAS Mains Botany Paper 2010

IAS Prelims & Mains GS and Optional Lectures, Model Answers, and Notes at doorsteptutor.com.

Paper-I

Section – A

Q.1 Answer the following in about 150 words each:

  1. Give an account of Heterothallism in fungi.

  2. Describe the process through which the bacterial genes are transferred from one bacterium to another by the viruses.

  3. Comment on Heterospory in Pteridophytes and its evolutionary significance.

  4. How would you test the clonal fidelity of the micropropagated plants? Describe.

Q.2

  1. Discuss ecological significance of Lichens.

  2. Distinguish clearly between Keratinophilic and Thermophilic fungi.

  3. Draw labeled diagrams of transverse and longitudinal sections of sporocarp of Marsilea.

Q.3

  1. What are somaclonal variations? How are these utilized for crop improvement?

  2. What is the importance of Bacillus thuringiensis in the current efforts to raise crop productivity?

  3. Write a note on Psilotum as a living fossil.

Q.4

  1. Differentiate the archegonium of Funaria from that of Anthoceros.

  2. With suitable examples, briefly describe the microbial processes occurring in the rhizosphere which help in plant growth.

  3. Five different types of spores are produced by the rust fungi. Mention their names and their salient points of distinction from each other.

Section – B

Q.5 Answer any three of the following in not more than 200 words each:

  1. Origin of angiosperms from gymnosperms is suggested on the basis of vessels. Give your critical comments.

  2. Describe the development of pollen exine and point out the role of sporopollenin.

  3. Name five edible oil yielding plants. Give their botanical names and families.

  4. Describe the fructification in Williamsonia.

Q.6

  1. With the help of labeled diagrams, compare the female gametophyte of Cycas with that of Gnctum.

  2. What are the changes that occur during the conversion of sapwood into heartwood? Which is more durable sapwood or heartwood. And why?

  3. Discuss whether the angiosperms are monophyletic or polyphyletic.

Q.7

  1. Give an account of the main events in the differentiation of a tracheary element.

  2. Give the botanical names of the plant species, their families, part used the uses of annatto and haematoxylin.

  3. Define agamospermy. What is its significance in crop improvement?

Q.8

  1. Describe the structure and function of synergids in angiosperms.

  2. With suitable examples, enumerate the floral characteristics of bird pollinated trees.

  3. Compare the androecium in the following groups of families:

  1. Malvaceae and Fabaceae
  2. Asclepiadaceae and Asteraceae
  3. Solanaceae and Brassicaceae

Paper-II

Section – A

Q.1 Explain any FOUR of the following in about 150 words each:

  1. Signal transduction in Prokaryotes
  2. Spontaneous mutations
  3. RFLPs
  4. Origin of mitochondria
  5. Normal distribution.

Q.2

  1. Explain FISH technique and its importance in understanding genomic relationships among species.

  2. Distinguish between:
  3. Smooth and rough ER

  4. Ribosomes and Peroxisomes

  5. Membrane proteins in ion transport.

Q.3. Differentiate between:

  1. Negative and positive gene regulation.

  2. Homologous and Heterologous recombinations.

  3. Exons and Introns.

  4. Transition and Transversion.

Q.4

  1. Describe in detail the Agrobacterium-mediated gene transfers in the development of transgenic crop plants.

  2. Describe the method of developing maize hybrids.

Section – B

Q.5 Explain any FOUR of the following in about 150 words each:

  1. Secondary metabolites and plant protection
  2. Photolysis of water
  3. Calcium in plant growth
  4. CDM
  5. Progressive ecological efficiency.

Q.6

  1. How would you distinguish between enzymes and co-enzymes?

  2. Differentiate between climacteric and non-climacteric fruits.

  3. Explain the process of fruit ripening and its regulation.

Q.7

  1. Explain photo-receptors and their role in regulation of plant growth.

  2. There are exceptions to the ecological phyramids. Explain.

  3. Explain the role of surface run-off in nutrient budget of ecosystems.

Q.8

  1. Mention the attributes of a species to make it invasive.

  2. Describe the role of growth regulators in sex expression of plants.

  3. Mention the ‘hot spots’ of India, and the reasons to recognize them as hot spots.

  4. ‘Feedback loops’ are the regulatory mechanisms that determine whatever changes take place in the ecosystem. Explain.