BIO/V/05 Student's Copy
2 0 1 8
Pre-CBCS
5th Semester
BIOTECHNOLOGY
Paper BT-V
Molecular Biology
Full Marks 55
Time 2½ hours
PART A—OBJECTIVE
Marks 20
The figures in the margin indicate full marks for the questions
SECTION—A
Marks 5
Tick the correct answer in the brackets provided 1×5=5
1. The basic nature of histone is due to the high percentages of
arginine and glutamine
lysine and arginine
arginine and cystine
lysine and alanine
/337 1 Contd.
2. Which of the following enzymes remove supercoiling in replicating DNA?
Polymerases
Nucleases
Topoisomerases
Primases
3. The 5¢ end of the mRNA contains
methylguanosine cap
methyladenosine cap
methylcytosine cap
None of the above
4. Protein synthesis requires
mRNA
rRNA
tRNA
All of the above
5. A mutation that results in change in the activity of fully synthesized
protein is
missense mutation
non-sense mutation
silent mutation
neutral mutation
BIO/V/05/337 2 Contd.
SECTION—B
Marks 15
Write short notes on the following 3×5=15
1. Mitochondrial genome
2. Okazaki fragments
3. Prokaryotic RNA polymerase
4. Proteins involved in protein folding
5. Base analogs
PART B—DESCRIPTIVE
Marks 35
The figures in the margin indicate full marks for the questions
1. Describe the Hershey and Chase's experiment in detail.
OR
Describe how Avery and his colleagues identified DNA as Griffith's
transforming principle. 7
2. Explain the experimental evidence to prove DNA replicates in
semi-conservative mode. 7
OR
Elucidate the mechanism of initiation of DNA replication in eukaryotes.
3. Explain in detail how mRNA is exported out of the nucleus into the
cytoplasm. 7
OR
Describe the trans-esterification reactions involved in RNA splicing.
BIO/V/05/337 3 Contd.
4. Mention in detail the characteristics of genetic code. 7
OR
Describe any two post-translational changes that modify protein behaviour.
3½+3½=7
5. Elucidate the nucleotide excision repair mechanism in E.coli with a labelled
diagram. 7
OR
Write a note on spontaneous mutations.