M.Sc. (Semester II) (CBCS) Examination Mar/Apr-2018
Microbiology
MICROBIAL GENETICS
Time: 2½ Hours
Max. Marks: 70
Instructions: Part- Questions 1 is Compulsory. Attempt any 4 questions from Part II. Figures to the right indicate full marks. Answer to the Part I and Part II are to be written in same answer booklet only.
PART I
Q.1
Choose the correct alternative given in the bracket.
14
Helix unwinding during replication in accomplished by
DNA helicases
DNA gyrase
DNA polymerase I
DNA polymerase II
The term plasmid was coined by
Tatum
Ochoa
Lederberg
Delbruck
Coordinated regulation of a function in bacteria is brought about by regulation of synthesis of poly cistronic mRNA regulated through
A single signal
Many signals coordinated by Rho
Double signal
Many signal molecules regulated by sigma factor
The term plasmid was coined by
Tatum
Ochoa
Lederberg
Delbruck
Proofreading and mismatch repair in DNA is carried out by
DNA polymerase I
DNA polymerase II
DNA polymerase III
Exonuclease
Amplification of plasmids is carried out by
Penicillin
Streptomycin
Chloramphenicol
Tetracycline
In PCR DNA polymerase is used.
Type I
Type II
Type III
Type IV
In one minute DNA polymerase I can add about
150 bases
300 bases
600 bases
1200 bases
SOS response brings to halt
DNA synthesis
RNA synthesis
Protein Synthesis
Carbohydrate synthesis
Page 2 of 2
SLR-UQ-535
10) Transposons can be delivered to bacteria through
Phages plasmids
Pili
Flagella
None of these
11) enzyme produces negative superhelicity and removes the positive superhelicity developed during replication.
Topoisomerase
DNA gyrase
DNA polymerase I
DNA polymerase II
12) Transposon Tn5 carries gene for resistance.
Kanamycin
Ampicilline
Penicillin
Chloramphenicol
13) In A form of DNA, one turn of helix consists of base pairs.
10
11
9.33
8
14) Removal thymine dimers is done by
DNA polymerase I
DNA polymerase II
DNA polymerase III
Exonuclease
PART II
Q.2
Explain types, properties and mechanism of transposition of transposable elements.
14
Q.3
Describe in detail the process of transcription in prokaryotes and add a note on post transcriptional process.
14
Q.4
Give the detailed account of deciphering of genetic code and its properties,
14
Q.5
Attempt any two of the following:-
14
Explain the techniques of gene sequencing.
Discuss the various enzymes involved DNA replication.
Describe operon model with reference to Tryptophan operon.
Q.6
Write short notes on any Two of the following:
14
Split gene and overlapping gene
SOS repair
Detection and purification of plasmid.