IAS UPSC (CSE) Mains 1985: Botany

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Paper-I

Section A

  1. Answer any three of the following. Answer to parts b & c should not exceed 200 words each:
    1. Write the correct technical term for the following:
      1. Aquatic free floating algae characterized by a median constriction that divides the cell into two halves.
      2. The first formed mechanical tissue of stems composed of elongated cells thickened only at the angles by cellulose.
      3. The condition of a flower in which bases of stamens, petals and sepals are fused into a hypanthium, that surrounds but is not fused to the pistil.
      4. A sterile filament unicellular or multicultural and interspersed among gametangia or sporangia.
      5. The basal enlarged portion of the female gametangium in Archegoniatae.
    2. In what important ways does the reproductive cycle of Ulva differ from that of Ulothrix? Explain the significance that this may have with respect to higher land. Plants.
    3. Where does karyogamy occur in Accomycetes and Basidiomycetes? How does this differ in Phycomycetes?
  2. Answer the following questions
    1. Make a critical comparison of the reproductive cycle of Marsilca with that of Pteridium.
    2. Give a brief account of the role of microbes in industry and agriculture.
  3. Answer the following questions
    1. Explain in what important respects Cycadeoids differ from Cycads. Why have Cycadeoids been proposed as ancestors to the flowering plants?
    2. iscuss the evolutionary relationship of the class Gnetopsida.
    3. What are downy mildews? Describe the disease cycle of any of the diseases caused by them and also give its control measures.
  4. Answer the following questions
    1. Describe the unique characters of Rhyniophtya and discuss the evolutionary trends.
    2. Bring out the special features of the three evolutionary series in brown algae and discuss the pattern of life cycle of each.

Section B

  1. Answer any three of the following. Answer should not exceed 200 words for each part.
    1. What is extrastelar cambium? Describe briefly the activity of such a tissue using any two specific examples.
    2. Discuss briefly the different type of endosperm formation. Explain the structure and fate of endosperm.
    3. What are the International Rates of Botanical Nomenclature? When were they propounded? Let the main principles involved.
    4. Explain photo morphogenesis and its regulation.
  2. Discuss any two of the following:
    1. The process of angiosperm in microsporogenesis.
    2. The secondary growth in a dicotyledonous root.
    3. The role of protoplast culture in plant improvement.
  3. Describe the uniqueness of the following:
    1. Flower in Asteraceae.
    2. Inflorescence in Euphorbiaceae.
    3. Gynoecium in Rosaceae.
    4. Androecium in Cucurbitaceae.
    5. Spikelet in Gramineae.
  4. Answer any three using not more than 200 words for each part:
    1. What are the salient features of the system of classification proposed by Takhtajan? How does it compare with that of Engler?
    2. Explain the unique features of the family Liliaceous. Discuss its phylogeny.
    3. Discuss the role of photochemistry in the classification and the determination of interrelationships.
    4. Describe with diagrams the process of fertilization in angiosperms and explain the seed development.

Paper-II

Section A

  1. Answer any three of the following using not more than 200 words for each part:
    1. Describe the chemical composition of cell-wall.
    2. Explain belling՚s hypothesis and copy choice.
    3. Explain functions of histones.
    4. Sketch the ulrrastructure of chloroplast. Briefly state the function of each component.
  2. Describe sexduction in bacteria. What is meant by reverse transcription? How is it regulated?
  3. Outline the procedures you adopt to isolate biochemical mutants of a microorganism. Describe chromosome puff.
  4. Answer any three of the following:
    1. What is hyper auxiny? Give two examples and their significance.
    2. Define proton motive force. What function does it sub serve in the mitochondria?
    3. Protoplast fusion and its relevance in the improvement of plants.
    4. Acid rain.

Section B

  1. Answer any three of the following in not more than 200 words for each part:
    1. What proportion of all genes causing hemophilia
    2. Describe the theories on the mechanism of stomata opening.
    3. What is meant by genetic engineering? Give four major applications.
    4. Discuss the significance of dispersal and migration in evolution.
  2. Describe the anaerobic transformation of glucose in organisms.
  3. Answer the following questions
    1. Write critically on ecological niche.
    2. Name two major sources of vegetable fats. Mention the names of four States in which the vegetable fat yielding plants are grown. Give four uses of fats.
    3. Trade the origin of wheat.
  4. Answer the following questions
    1. What methods will you suggest for control of environmental pollution?
    2. Outline the carbon cycle in nature.