GPB Qualifying Examination (Semester of 2013–14)

Directorate of Post Graduate Studies, GKVK, Bangalore – 65
Department of Genetics and Plant Breeding
Qualifying Examination (I Semester of 2013–14)
Duration: 3 ½ Hours  Maximum Marks: 100

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❖ Section I: Define (Answer 10 out of 12)

One mark each — 10 × 1 = 10

1. A genetic pedigree showing that only males are affected by a certain disorder is an evidence of what type of inheritance?

2. Define epistasis.

3. What are sex-limited characters?

4. Role of spindle apparatus in mitosis

5. Transgressive segregation

6. Restorer lines

7. Principal Component Analysis

8. What is photoelectric absorption?

9. Point Mutation

10. Define translocation.

11. Define epigenetics.

12. BLAST

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❖ Section II: Answer the following (10 out of 12)

Two marks each — 10 × 2 = 20

1. Differentiate between multiple alleles and multiple loci

2. Give the genotypes for Parent, F1, and F2, based on the phenotypes given in the table:

Raobi Test Cross Results

Generation	Cross	Result
Parent Generation	Black × White	—
F1	All Black	Aa
F2 (Test cross)	75% Black, 25% White	Aa × Aa → Aa, aa

3. What are Y-linked characters? Explain the inheritance of one holandric character in human beings.

4. What is meant by inbreeding depression? Give examples of repairing mechanisms operating at DNA level.

5. Limitations of mutation breeding

6. Significance of genetic drift in evolution

7. Illustrate megagametogenesis

8. Explain different types of heterosis

9. Differentiate horizontal and vertical resistance

10. What is the difference between physical and genetic map?

11. What are two types of inversions in chromosomal aberration?

12. Principles of path coefficient analysis

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❖ Section III: Write short notes (10 out of 15)

Three marks each — 10 × 3 = 30

1. Law of independent assortment — explain

2. Differentiate qualitative and quantitative traits

3. Enumerate the steps involved in hybrid development

4. Disease control through use of multilines — explain with example

5. How can you overcome fertilization barriers through in-vitro techniques?

6. Give details on theories of crossing over

7. How will you maintain the Genetic Male Sterile (GMS) lines with diagram?

8. Software used for:

   1. Gene annotation

   2. Primer designing

   3. ORF prediction

   4. Genome map

   5. Protein database

   6. Multiple alignment

9. Explain the use of nanotechnology in disease diagnosis

10. Under what situations should a breeder opt for mutation or transgenic breeding? List the merits and demerits.

11. How will you calculate the G × E interaction? Explain with one analysis.

12. Significance of apomixis in crop improvement

13. Different methods of conservation of plant genetic resources

14. Describe any two mating designs for predicting epistasis gene action

15. Differentiate between:
    a. Nullisomic and Tetrasomic
    b. Alloploidy and Amphidiploidy

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❖ Section IV: Long Answer Questions (Answer 8 out of 12)

Five marks each — 8 × 5 = 40

1. Explain gene mapping and its application in crop improvement

2. What is criss-cross inheritance? Explain the inheritance of one sex-linked recessive character in humans

3. What approaches are used for detecting the number of copies of a transgene in a transgenic plant? How will you genetically stabilize a transgenic line?

4. Discuss the different methods of production of haploids in plants with their merits and demerits. Compare use of haploids in breeding and gene mapping to conventional methods.

5. Discuss co-dominant markers. List some co-dominant markers and their significance in crop improvement.

6. Discuss the role of aneuploids in basic and applied aspects of crop breeding.

7. Write short notes on the following:

   1. a) Golden rice

   2. b) Cry proteins

   3. c) Gene silencing

   4. d) Biofortification

8. Explain mating designs used to detect di-genic epistasis

9. Compare the different male sterile lines and their application in crop improvement

10. Write various mutagenic agents and their mechanisms of action in inducing mutation

11. Briefly explain the model of chromosome structure

12. Enumerate the applications of plant tissue culture — a potential tool for plant breeders