Course No. PBG 201 Max Marks : 50Course title : Elements of Genetics and cytogenetics

I. (10.00 marks)A. Choose the correct answer (10 x 0.5= 5.0)1. the operon concept was proposed bya. Jacob and Monad b. Leewenhock c. Punnet d. Khorana2.The F2 segregation ratio for inhibitory gene interaction isa. 13:3 b. 15:1 c. 9:3:4 d. none of these3. Father of genetics isa. Bateson b. |Darwin c. Mendel d. None of these4. Self incompatibility is an example for a. multiple alleles b. psueodallelels c. multiple genes d. all of these5. Mutation theory was put forth bya. de Vries b. Muller c. Morgan d. none of these6. the term okazaki fragment is associated witha. DNA replication b. transcription c. translation d. all of these7.the hypothesis of acquired characters was proposed bya. Weissman b. Lamarck c. Mendel d. Darwin8. Initiation codon is a. AUG b. ATG c. UUU d. AGU9.The maximum per cent of crossing over that can occur in any cell is

a. 50 b.100 c. 0 d. 2510.The number of linkage groups in Zea mays

a. 10 b. 20 c. 2 d. 1

B. Match the following (10 x 0.5 = 5.0)1. Complete linkage a. duplicate genes2. Theory of evolution b. somatic cell3. 15: 1 c. no crossing over4 .nullisomics d. Y chromosome5. autosome e. cytoplasmic male sterility6. holandric genes f. Y chromosome7. self incompatibility g. chiasma formation8. mitochondria h. darkly stained9. crossing over i. 2n -210. heterochromatin j. multiple alleles

II. Define the following (10 x 1.0 = 10.0)1. Pleiotropism2. aneuploidy3. translocation4. anticodon5. m RNA

6. sex linkage7. allele8. endomitosis 9. anaphase10. additive genes

III. Write short notes on any five of the following (5 x 2.0 = 10.0)

1. deletion and duplication2. coupling and repulsion3. genetic map4. multiple alleles5. forward and reverse genetics 6. reason for existence of differences among cells arising from meiosis and not

arising from those from mitosis

IV . answer any four of the following (4 x 2.5 = 10.0)

1. Write the role of linkage in evolution 2. Differentiate sex linked and sex limited characters3. Write about different types of mutation4. Write about breeding behaviour of translocation heterozygote5. Write in brief about maternal inheritance with a suitable example

V answer the following (4+3+3=10.0)

1. Explain multiple factor hypothesis with Nilson Ehle ’s experiment2. Describe the different steps involved in protein synthesis

(OR)Discuss the Mendel’s Laws of inheritance and list out the characters studied by Mendel

3. Write in brief about special types of chromosomes(OR)

Discuss about various types of lethal genes

Tamil Nadu Agricultural UniversityAnbil Dharmalingam Agricultural College & Research Institute

B.sc (Agri) Degree ProgrammeModel question paper

AGB: 201 – Genetics and cytogenetics

PART-A

1. Darwin’s theory2. Heredity3. Centromere4. Law of dominance5. Phenotype6. Epistasis7. Self incompatibility8. Poly genes9. Linkage types10. Crossing over11. Types of sex determination12. DNA13. Types of RNA14. Cistron15. Special types of chromosomes16. Deletion17. Monosomy18. Polyploidy19. Examples for polyploidy crops20. Nucleus21. Different stages in prophase 1 of meiosis22. Characters studied by Mendel23. Strength of linkage24. Genetic map

PART-B

1. Distinguish between Quantitative and qualitative characters2. Differentiate Backcross and test cross3. Sex determination in papaya4. Differentiate Isoallele and Pseudoallele5. Structure of mitochondria6. Characteristic feautures of cytoplasmic genes7. Draw the diagram of DNA(Watson& Grick) model8. Write short notes on chromosome based on position of centromere9. Mendel’s dihybrid test10. Give the classification of Epistasis

11. Complete linkage12. Significance of crossing over 13. Differentiate Dominance and Epistasis14. Characters of sex linked inheritance15. Write a short notes on central dogma16. What is operon model17. Write the importance of numerical variation OF chromosome18. Explain the evolution of Cotton19. Differentiate DNA and RNA20. Significance of Meiosis21. Discus double cross over22. Difference between prokaryote And eukaryote cell23. Briefly describe karyiokinensis of Mitosis24. What is co dominance write an example

PART-C

1. What is polyploidy? Write about different kinds of polyploids2. Draw the neat sketch of Different stages of Mitosis3. State the law’s of Mendel and explain the law of independent assortment4. What is multiple allele? Explain it with example 5. Write the functions of following a)Chloroplast)Mitochondria)Ribosome’s)Plasma

membrane and e) cell wall6. What is sex linked inheritance? Discus it with example7. Describe the structure of DNA (Watson& Grick model)8. Describe the NelsonEheles experiment on multiple alleles9. What is linkage and how it is estimated10. Explain the chromosomal Sex determination11. Explain co dominance and over dominance with example12. Explain Protein synthesis13. Discus the cytological basis of crossing over14. What are Chromosomal aberrations? Describe deletion and duplication15. Explain the Griffith’s experiment16. Discus the operon model