Genetics and Molecular Biology (DSC-2, Botany-02) — DU B. Sc. Life Science (Botany) Previous Year Question Papers

All parts of a question must be answered together. 1. a) Define the following: (any five) i. Variation ii. Tandem duplication iii. Suppressor mutation iv. Genotype v. Allele vi. Autopolyploidy b) Give one significant contribution of the following: (any five) i. George Beadle and Edward Tatum ii. François Jacob and Jacques Monod iii. Alfred Hershey and Martha Chase iv. Thomas Hunt Morgan v. William Bateson and Reginald Punnett vi. Carl Correns c) Expand the following: (any five) i. 5-BU ii. ORF iii. NTP iv. F1 2. Write short notes on the following: (any three) i. Chemical mutagens ii. Chromosomal theory of inheritance iii. Central dogma of Molecular Biology iv. Turner’s syndrome 3. Differentiate between the following: (any three) i. Rho-dependent and rho-independent termination of transcription ii. Pericentric and paracentric inversion iii. tRNA and mRNA iv. Euploidy and Aneuploidy 4. Draw a well-labelled diagram of the following: (any three) i. B-DNA ii. Chloroplast inheritance iii. Replication fork iv. Ancestry of wheat 5. Answer the following: 8+7=15 i. Explain variations in chromosome number and structure with the help of well-labelled ii. diagrams. What is operon? Explain the working of Lac Operon with the help of suitable diagrams. 6. Attempt the following: 8+7=15 i. In a species tall (D) is dominant over dwarf (d), and blue flowers (W) is dominant over white (w). Consider two tall plants with blue flowers labelled A and B. Each was crossed to a dwarf plant with white flowers. The seeds resulting from each cross were collected and grown into F1 plants which showed the following phenotypic classes: ii. Progeny of A 151 tall, blue 149 dwarf, blue Progeny of B 74 tall, blue 76 tall, white 75 dwarf, blue 75 dwarf, white What were the genotypes of A and B? Diagram the cross. Define genetic code. Discuss Nirenberg and Matthaei’s experiment that led to the deciphering of genetic code.