W.B Civil Service Examination (Main)- 2000
(Optional Papers)
Botany Paper-I
Time Allowed-3 Hours Full Marks-100
Group - A
Answer any three questions
1. What is heterethallism ? Describe the phenomenon with reference to Mucor. Give an account of a fungus of medicinal importance. Name the active principle and mention its source. 2+6+8+4
2. What do you mean by Fungi Imperfacti ? Mention the causal organism of 'brown spot of rice". What are the symptoms observed ? How do you control the disease ? What are aflatoxius and phytoalexin ? 2+2+4+4+8
3. (a) Give a general account of the distribution of photosynthetic tissues in the members of bryophytes you have studied. 8
(b) Name one imprtant character by which thallophyta differs from bryophyta. 2
(c) State the structural differences between the spore bearing organs of Lycopodium and Equisetum. 6
(d) Mention the fern characters of Cycus. 4
4. (a) What do you understand by artificial and phylogenetic systems of classification of plants ? Discuss the principles on which these classifications are based. 4+6
(b) Compare the diagnostic characters of Schitamineae with those of Orchidaceae and indicate their systematic positions. 6
(c) Name the families to which the following plants belong and write down the type of inflorescence of each - (i) banana ; (ii) Wheat; (iii) Onion ; (iv) Coriander. 4
5. (a) Mention the growth forms of lichens with examples. Explain the symbiotic relationship of lichen. 6+2
(b) What is ovule ? State the different types of ovules found in angiosperms with examples. 2+6
(c) Mention the type and the edible parts of the following fruits: (i) apple; (ii) tomato; (iii) orange (iv) pomegranate. 1x4
Group - B
Answer any two questions
6. Write brief notes on any five of the following :
(a) Kock's postulate
(b) Genetic spiral :
(c) Hyperplastic symptoms ;
(d) Tetrasporic female gametoplyte ;
(e) Pyenoxylic wood ;
(f) Aggregate fruit ;
(g) Syngenesions and synandrous stamen. 4x5
7. Distinguish between the following pairs (any four) :
(a) Stipule and Stipel.
(b) Gram negative and gram positive bacteria.
(c) Virus and plasmid.
(d) Retrovirus and reovirus.
(e) Salk vaccine and Sabin oral vaccine.
(f) Virus and Viroid. 5x4
8. (a) Name two components of a bacterial cell wall which are not present in the cell wall of higher plants. 4
(b) What is pasteurization ? How can we count virus particles ? 2+2
(c) Describe the structural charaegteristies of monocotyledon seed. How does it differ from dicotyledon seed ? 4+2
(d) Discuss various theroies regarding the origin of angiosperms
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