MAHATMA GANDHI UNIVERSITY, KOTTAYAM, KERALA, INDIA
M.Sc. BOTANY DEGREE EXAMINATION, MAY 2005
Faculty of Sciences, Branch VI – Botany
PAPER – VI – CELL BIOLOGY, GENETICS AND PLANT BREEDING
Time: Three Hours Maximum: 75 Marks
Section A (Cell Biology)
I. Answer any seven of the following: (7 X 1 = 7 Marks)
1. Explain mitochondriopathy.
2. Explain the structure and function of spindle apparatus.
3. Explain a translocation heterozygote.
4. Explain satellite DNA.
5. Give an account on chromosome library.
6. Write notes on Philadelphia chromosomes.
7. Comment on plastomes.
8. Give an account on the role of extrinsic and intrinsic proteins.
9. Explain breakage-fusion-bridge-cycle
II. Answer any two of the following: (2 X 4 = 8 Marks)
10. What is karyotype concept? Explain the recent trends in karyotype.
11. Give an account of the numerical variables of chromosomes. Explain their genetic consequences.
12. Write an account on the effects of high energy radiations on chromosomes.
III. Answer any one of the following: (1 X 8 = 8 Marks)
13. Discuss the structural details of various types of supernumerary chromosomes and giant chromosomes. Mention their significance.
14. Describe the various numerical and structural variations of chromosomes. Explain their meiotic behavior
Section B (Genetics)
IV. Answer any five of the following: (5 X 1 = 5 Marks)
15. What do you mean by cot value?
16. Explain apoptosis.
17. What is gene erosion?
18. Explain modifiers and suppressors.
19. Write notes on genetic polymorphism.
20. Explain microsatellites.
V. Answer any three of the following: (3 X 2 = 6 Marks)
21. Describe the applications of variability analysis in quantitative inheritance.
22. Distinguish between pseudo-genes and crypto-genes.
23. Distinguish between proto-oncogenes and oncogenes.
24. Write notes on site directed mutagenesis.
VI. Answer any three of the following: (3 X 4 = 12 Marks)
25. Mention the principles, methods and applications of DNA fingerprinting.
26. Distinguish between Southern, Western and Northern blotting.
27. Categorize the different forms of DNA. How do they differ from each other?
28. Describe Polymerase Chain Reaction. What are its applications?
VII. Answer any two of the following: (2 X 7 = 14 Marks)
29. Give a detailed account of the regulations of gene expression in prokaryotes and eukaryotes.
30. Explain Hardy-Weinberg law and its applications. How is it useful in predicting gene frequencies in a population?
31. “Transgenesis involves genetic transformation by non-sexual means” – Evaluate.
Section C (Plant Breeding)
VIII. Answer any four of the following: (4 X 2 = 8 Marks)
32. How are allopolyploids formed? Discuss their role in the evolution of Wheat and Brassica.
33. What are the necessities of plant introduction? Cite important achievements of plant introduction as a breeding method.
34. “Genetic diversity is always essential for crop improvement” – Explain
35. “Triploids are more preferred among grapes, bananas and watermelons than diploids” – Discuss.
36. Describe the techniques and applications of resistance breeding in plants.
IX. Answer any one of the following: (1 X 7 = 7 Marks)
37. Describe in detail the recent molecular approaches for crop improvement.
38. Give an account of the various methods and achievements of mutation breeding in crop plants.