IAS UPSC (CSE) Mains 1985: Botany
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Paper-I
Section A
- Answer any three of the following. Answer to parts b & c should not exceed 200 words each:
- Write the correct technical term for the following:
- Aquatic free floating algae characterized by a median constriction that divides the cell into two halves.
- The first formed mechanical tissue of stems composed of elongated cells thickened only at the angles by cellulose.
- 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.
- A sterile filament unicellular or multicultural and interspersed among gametangia or sporangia.
- The basal enlarged portion of the female gametangium in Archegoniatae.
- 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.
- Where does karyogamy occur in Accomycetes and Basidiomycetes? How does this differ in Phycomycetes?
- Write the correct technical term for the following:
- Answer the following questions
- Make a critical comparison of the reproductive cycle of Marsilca with that of Pteridium.
- Give a brief account of the role of microbes in industry and agriculture.
- Answer the following questions
- Explain in what important respects Cycadeoids differ from Cycads. Why have Cycadeoids been proposed as ancestors to the flowering plants?
- iscuss the evolutionary relationship of the class Gnetopsida.
- What are downy mildews? Describe the disease cycle of any of the diseases caused by them and also give its control measures.
- Answer the following questions
- Describe the unique characters of Rhyniophtya and discuss the evolutionary trends.
- Bring out the special features of the three evolutionary series in brown algae and discuss the pattern of life cycle of each.
Section B
- Answer any three of the following. Answer should not exceed 200 words for each part.
- What is extrastelar cambium? Describe briefly the activity of such a tissue using any two specific examples.
- Discuss briefly the different type of endosperm formation. Explain the structure and fate of endosperm.
- What are the International Rates of Botanical Nomenclature? When were they propounded? Let the main principles involved.
- Explain photo morphogenesis and its regulation.
- Discuss any two of the following:
- The process of angiosperm in microsporogenesis.
- The secondary growth in a dicotyledonous root.
- The role of protoplast culture in plant improvement.
- Describe the uniqueness of the following:
- Flower in Asteraceae.
- Inflorescence in Euphorbiaceae.
- Gynoecium in Rosaceae.
- Androecium in Cucurbitaceae.
- Spikelet in Gramineae.
- Answer any three using not more than 200 words for each part:
- What are the salient features of the system of classification proposed by Takhtajan? How does it compare with that of Engler?
- Explain the unique features of the family Liliaceous. Discuss its phylogeny.
- Discuss the role of photochemistry in the classification and the determination of interrelationships.
- Describe with diagrams the process of fertilization in angiosperms and explain the seed development.
Paper-II
Section A
- Answer any three of the following using not more than 200 words for each part:
- Describe the chemical composition of cell-wall.
- Explain belling՚s hypothesis and copy choice.
- Explain functions of histones.
- Sketch the ulrrastructure of chloroplast. Briefly state the function of each component.
- Describe sexduction in bacteria. What is meant by reverse transcription? How is it regulated?
- Outline the procedures you adopt to isolate biochemical mutants of a microorganism. Describe chromosome puff.
- Answer any three of the following:
- What is hyper auxiny? Give two examples and their significance.
- Define proton motive force. What function does it sub serve in the mitochondria?
- Protoplast fusion and its relevance in the improvement of plants.
- Acid rain.
Section B
- Answer any three of the following in not more than 200 words for each part:
- What proportion of all genes causing hemophilia
- Describe the theories on the mechanism of stomata opening.
- What is meant by genetic engineering? Give four major applications.
- Discuss the significance of dispersal and migration in evolution.
- Describe the anaerobic transformation of glucose in organisms.
- Answer the following questions
- Write critically on ecological niche.
- 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.
- Trade the origin of wheat.
- Answer the following questions
- What methods will you suggest for control of environmental pollution?
- Outline the carbon cycle in nature.