[Total Time: 2½ hr.]
[Total Marks: 75 ]
1 Attempt all questions.
2. All questions carry equal marks.
3. Draw neat labeled diagrams wherever necessary.
4. For Q 2, Q 3, and Q 4 attempt A and B OR Cand D.
Q. 1 Do as directed: (Any fifteen) (15M)
1) ____________ catalyzes the polymerization of nucleotide precusors into a DNA chain.
2) The direction of synthesis oī the new DNA chain is only from ___________ direction becāuse of the properties of DNA polymerase
3) The enzyme DNA polymerase I in E.coli is encoded by the _______________ gene.
4) Replication of prokaryotic and viral DNA usually starts at a specific site on the chromosome called ______________.
5) The physical untwisting of the DNA is catalyzed by the enzyme ____________.
6) The complex of the primase and the helicase with the DNA is called the ____________.
7) In eukaryotes, the enzyme _____________ catalyzes the mitochondrial DNA replication.
8) State True or False: Nitrous acid is a Base modifying agent.
9) Define: Mutagens.
10) What is a tautomeric shift?
11) Give one example of a lionizing radiation-inducing mutations.
12) Name the enzyme catalyzing Photoreactivation.
13) _____________is a regulator protein involved in induction of the SOS response.
14) Name of the plasmid present in Agrobacterium tumefaciens.
15) Role of multiple cloning sites.
16) State True or false; Conjugation requires physical contact between two cells.
17) State True or false: The microinjection technique is used to introduce genes into a eukaryotic cell.
18) Give the name of one marker gene.
19) State any one role of DNA ligases.
20) Give one example of a Prokaryote used for cloning,
Q. 2) A) Elaborate the key steps involved in DNA replication in prokaryotes. (8M)
Q. 2) B) Explain Meselson and Stahl’s experiment to prove replication of DNA is semiconservative. (7M)
Q. 2) C) Explain initiation of replication of DNA in Eukaryotes. (8M)
Q. 2) D) Diagrammatically explains the model for reciprocal recombination. (7M)
Q. 3) A) Define Mutation. Give general classification of Mutation. (8M)
Q. 3) B) Explain Base Excision Repair. (7M)
Q. 3) C) Discuss various types of base pair substitution mutations. (8M)
Q. 3) D) Diagrammatically explains mutagenic action of 5- bromouracil. (7M)
Q. 4) A) How did Hershey and Chase prove that DNA is the genetic material of the cell? (8M)
Q. 4) B) Discuss the Discovery of RNA as a genetic material (7M)
Q. 4) C) Describe the features of pUC vector. (8M)
Q. 4) D) Explain any one mode of gene transfer in. prokaryotes. (7M)
Q. 5) Write short notes on (Any three) (15M)
a) SSB proteins
b) Rolling circle replication of DNA
c) Mütation caused by UV rays.
d) Shuttle Vectors
e) Alkaline phosphate. Source and uses.