W.B Civil Service Examination (Main)- 2003
(Optional Papers)
Botany Paper-II
Time Allowed-3 Hours Full Marks-100
Group - A
Answer any three questions
1. (a) How do you differentiate prokaryotic and eukaryotic chromosomes ? 3
(b) Enumerate the double-helical sturcture of DNA with diagram. 5
(c) Write a brief note on the morphology of chromosomes. 5
(d) Define karyotype. What do you know about ideogram ? 3
(e) Write in brief about the different types of alterations to chomosome nubers. 4
2. (a) What is "Cental Dogma" ? 2
(b) Write the different speps of the initiation phase of translation in prokaryotes. 5
(c) How the gene expression is regulated in case of "lac operon" in E. coli bacterium ? 5
(d) Write a brief note on the secondary structure of proteion. 5
(e) Mention the characteristic propertises of rfunctional proteins. 3
3. (a) What is "redox-potential" ? 2
(b) What is the role of this redox- rptentialin synthesizing ATP during photophosphory lation ? 4
(c) State the role of Red drop and Emerson's ebhancement Effect in determining two diffeent pigment systems in plants. 4
(d) Ebiween two key enzymes of photosynthesis, namely Rubisco and pepcase, which one acording to you is moe efficient ? Give reasons in favour of our comment. 5
(e) Write the Blaekman's Law of Limiting Factos. Explain the law in your own wods. 5
4. (a) Who discovered the electron microscope? State the significance of this discovery in Cell Biology. 2
(b) Which piiint cell organelle is called lansducer and why ? 2
(c) Which organelle in plant cell is responsible for protein synthesis ? with labelled diagram describe its structure. 6
(d) Explain the mechanism of Osmosis with reference to Gibbs free energy concept. What do you know about water potential ?
(e) State one experiment to show that absorption rate n plants -is directly related to transpiation rate of that respective plant. 5
5. (a) What are Chargaffs rules ? 3
(b) How can you prove that the genetic material is DNA in natue but not protein ? 4
(c) How can a structural alteration of a hromosome be delected by looking at the chrmosomes through a microscope ? 4
(d) A, B, C, D are four loci of the same chromosome. Their recom-bination in beteween A and B, B and C, C and D, A and C, B and A, and D are respectively 5, 17, 18,12, 1 and 6. Map these four loci according to their crossover percentatges on the same chromosme. 5
(e) What is micro-evlufion ? Mention the names of agents which are responsible for micro-evolution. 2
Group-B
Answer any two questions.
6. (a) Define "standing crop" and " standing state". 2
(b) Describc two pyramids of numbers, one being straight and other one inverted. 5
(c) What is ecological niche ? 2
(d) Write a short note on unidirectional How of energy in eco-systems. 5
(e) What is allogenic sucession ? Give a brief account of the various stages of a specific sere upto climax formation. 6
7. (a) Give the botanical, names of any Uieree of the following with their respective families, parts used and economic importances of die following :
(i) Bottle gourd, (ii) Emblic (Amla), (iii) Clove, (iv) Para rubbber or Hevea Rubber. 4 x 3 = 12
(b) Give die names of two new varieties of wheat which have been successfully introduced recently. Mention the names of two diseases of wheat with causal organisms and respective pests.
8. Write short notes on any five of the following:
(a) Arsenic hazard in West Bengal
(b) Microclimate mid ecological indicators
(c) Bcotone
(d) Synusia
(e) Phytogeogaphical regions of India
(f) Camellia sinenis - the pride of India.
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