WEST BENGAL CIVIL SERVICE
EXAMINATION - 2006
Time Allowed-3 Hours Full Marks-100
Group - A
(Answer any three questions.)
1. What is meant by 'Meta genesis' ? Explain it with diagrams and references to the life cycle, of Obelia. Comment on how a Medua is derived from polyp. 2+3+10+5
2 Write in brief the anatomical peculiarities of Limulus. Discuss the affinities of Limulus. 10+10
3. What is venous heart ? Draw a venous heart of a teleost fish. Describe the method of purification and mode of circulation of blood in 'teleost fish.' 3+5+6+6
4. What is meant by double respiration ? Draw a neat diagram and describe double respiration with reference to the respiratory system of birds. 5+5+10
5. Write short notes on any four of the following :- 5x4
(a) Modes of locomotion in Paramaecium.
(b) Distinguishing characters of Phylum Cnidaria.
(c) Flame Cells,
(d) Scolex of Taenia Solium,
(e) Trachea of Cockroach,
(f) Rectrices and remiges.
Group - B
(Answer any two questions.)
6. What is lac ? Write its composition. Name the strains of lac crop with their characters. Write on natural and artificial methods of inoculation. What are the uses of lac ? 2+2+4+8+4
7. What is "Community dominance" ? Give an account of the ecological niches and state how niche differes from habitat. What is ecological succession ? Give an account of the ecological succession in a pond. 3+3+3+2+9
8. Write short notes on any four of the following :- 5+4
(a) Food chain and food web.
(b) Precautions to be taken during the cultivation of silk,
(c) Diseases of honey bees and their symptoms,
(d) Exotic fish culture,
(e) Organo phosphate insecticides.