LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034
M.Sc. DEGREE EXAMINATION – BIO TECHNOLOGY
FIRST SEMESTER – APRIL 2007
IB 20
BT 1815 - CELL & MOLECULAR GENETICS
Date & Time: 30/04/2007 / 1:00 - 4:00
Dept. No.
Max. : 100 Marks
Part – A
I. Choose the correct answer
(20 marks)
(5 X 1 = 5)
1. Which of the following is considered as a microfilament poison?
a) colchicine
b) cytocholasin
c) kinesin
d) dynein
2. The direction of replication in Okazaki fragment is
a) 5’
3’
b) 3’
5’
c) nonspecific
d) random
3. What is the function of poly (A) tail?
a) transport
b) stability
c) coding
d) translation
4. The enzyme involved in photo reactivation is
a) photolyase
b) polymerase
c) transcriptase
d)ligase
5. Percentage of crossing over between two linked genes of distance one map unit is
a) 1%
b) 2%
c) 100%
d) 200%
II. State true / false, if false, correct the statement.
(5 X 1 = 5)
6. GTP is utilized in the movement of dynein arm.
7. RNA secondary structure is linear.
8. Introns are the only coding sequence in the gene.
9. Amino acid change due to mutation is called nonsense mutation.
10. Back crossing with the dominant parent is called test cross.
III. Complete the following
11.
12.
13.
14.
15.
Extensins are glycoproteins with ------- charge.
Inverted repeats in mitochondrial genome cause --------.
---------- signals the termination of transcription.
F in F1 is called ---------.
The appearance of intermediate character in F1 generation is known as --------.
IV. Define the following.
16.
17.
18.
19.
20.
(5 X 1 = 5)
SAR
Nucleosome
Splicing
Recombination
Transition
(5 X 1 = 5)
Part – B
Answer any five questions within 250 words.
21.
22.
23.
24.
25.
26.
27.
28.
(5 X 8 = 40)
Discuss the structure and composition of ribosomes.
Explain the characteristic features of fluid mosaic model of plasma membrane.
Draw the structure of mRNA and explain the function of its components.
Write briefly on cell cycle. Explain the role of M-cdk complex.
Define Shine Dalgarno sequence. Discuss translational apparatus in protein synthesis.
Define transformation. Explain the phenomenon in Gram positive bacteria.
Explain gene regulation with lac operon.
Discuss incomplete linkage in drosophila with an example.
Part – C
Answer both questions within 1200 words.
(2 X 20 = 40)
29. a). What is cell signaling? Explain the intracellular and cell surface communication
with an example.
(12)
b). Draw the structure of nuclear pore complex and explain.
(8)
or
Explain the role of individual proteins in the replication of a eukaryote. Discuss
replication initiation and elongation of Okazaki fragments.
(20)
30. Define a gene. Explain various slicing mechanisms in eukaryote.
(20)
or
Write short notes
a). Mutation
b). DNA repair mechanism.
c). Chloroplast inheritance in variegated four ‘O’ clock plant
d). Codominance.
(4 X 5 = 20)