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BOTANY
Paper-II

Time Allowed: Three Hours

Maximum Marks: 250

QUESTION PAPER SPECIFIC INSTRUCTIONS
Please read each of the following instructions carefully before attempting questions.
There are EIGHT questions divided in Two Sections and printed both in HINDI and in ENGLISH.
Candidate has to attempt FIVE questions in all.
Question no. i and 5 are compulsory and out of the remaining, THREE are to be attempted choosing at least ONE from each section.
The number of marks carried by a question/part is indicated against it.
Answers must be written in the medium authorized in the Admission certificate which must be stated clearly on the cover of this Question-cum-Answer booklet in the space provided. No marks will be given for answers written in medium other than the authorized one.
Word limit in questions, wherever specified, should be adhered to. Diagrams/Figures, wherever required, shall be drawn in the space provided for answering the question itself.
Attempts of questions shall be counted in chronological order. Unless struck off, attempt of a question shall be counted even if attempted partly. Any page or portion of the page left blank in the answer book must· be clearly struck off.

SECTION-A

Giving reasons explain the consequences of 5XIO=5O

Q.I(a) Exposing polytene chromosomes to actinomycin.
Q.1(b) Illegitimate crossing over between a normal and an accessory chromosome. 10
Q.1(c) Intra allelic recombination.
Q.I(d) Removal of H1 histone from a cell.
Q.I(e) Exposing dividing cells to CdkI.

Q.2(a) Describe in detail the formation, structure and chemical composition of glycocalyx.20
Q.2(b) Citing a suitable example explain tripartite type of sex determination. I5
Q.2(c) Explain how GISH can be used for identifying the putative ancestors of a plant. I5

Q.3(a) "Genes do not arise de novo." Keeping in view this fact describe the phenomena that must have helped in increasing the number of genes during evolution. 20
Q.3(b) Where are CMS genes located and how ·do these act? What are restorer genes? I5

Q.3(c) With the help of any well established example explain how replacement of a purine by a pyrimidine can induce mutations. 15

Briefly describe characteristics and importance of the following 5x10=50

Q.4(a) Pachytene
Q.4(b) Neo-darwinism
Q.4(c) Balanced lethal system
Q.4(d) Chi-square test
Q.4(e) Linkage

SECTION-B

Q.5(a) What would you conclude if A previously lichen-rich area is now devoid of lichens.
Q.5(b) A species is added to the Red Data Book.
Q.5(c) Saffron corms transplanted to Delhi in December 2010 did not flower in 2011 and 2012.
Q.5(d) A plant exhibits kranz anatomy.
Q.5(e) A pond is totally covered with Eichornia.

Q.6(a) What are secondary metabolites What is their use to the plants and to the human beings? 20
Q.6(b) Describe various sub types of the most abundant biological molecule present in plants. 15
Q.6(c) What is the difference between afforestation and reforestation? What are the gains and pitfalls of monoculture in forestation practices 15

Q.7(a) Describe various phytogeographical zones and their characteristics in India. Give furtherdetails of the zone which experiences high temperatures, restricted snowfall and high rainfall, and has adundance of Rhododendrons, Ferns, Orchids and Oaks. 20
Q.7(b) Differentiate between growth, development and differentiation and describe the factors that influence these processes. 15
Q.7(c) Discuss how our understanding of stress physiology will help in mitigating problems expected to arise because of rapid changes in global environment. 15

Q.8 How are these accomplished 5xlO=50

Transport of solutes in phanerophytes.
Q.8(b) Proper planning before undertaking any developmental project to avoid its adverse impact on environment. 10
Q.8(c) Energy trapping. 10
Q.8(d) Overcoming seed dormancy. 10
Q.8(e) Control pollution by biotic means. 10