WBCS(Main)-2008 Zoology Paper-I Question Paper

                                                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