WEST BENGAL CIVIL SERVICE
EXAMINATION - 2008
Zoology Paper-I
Time Allowed-3 Hours Full Marks-100
Group - A
(Answer any three questions.)
1. Define metamorphosis and retrogressive metamorphosis। Explain the retrogressive and progressive changes in the life cycle of Ascidia. Give an example of non-chordate having retrogression in adult. (2+2)+(7+7)+2
2. Mention the course of water circulation in the canal system of Sycon. Name the various cells found in sponges. Write a note on the spicules in sponges with suitable diagrams. 5+5+10
3. Explain the comparative anatomy of kindney of fish, amphibia, reptilia and mammals. Add a note on the fate of ducts of the urogenital system in the course of evolution। 4x4+4
4. Elucidate the changes of nuclei in Paramoecium in the course of typical conjugation. Write on the significance of conjugation. Discuss on the detailed structure of cilia or flagella. 10+4+6
5. Write short notes on any four: 5x4
a. Swim bladder
b. Echolocation
c. Torsion
d. Cercaria
e. Polian vesicles
f. Mouth parts of Periplaneta.
Group - B
Answer any two
6. a. Explain the concept of fixed action pattern with suitable examples in terms of behaviour. 10
b. Define biological clock. Explain circadian clock with example. 2+8
7. Define gross and net productivity. Explain the factors influencing productivity. Explain energy flow with a suitable model. 2+2+8+8
8. Write scientific name of two pearl producing mollusks. Write the composition of pearl. How pearls are formed ? Explain the technique of pearl culture. 2+3+5+10
9. Define probability. Write on one-tail test and two-tail test. State the general properties of normal distribution. 4+8+8
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