4. BIOTECHNOLOGY: PRINCIPLES AND PROCESSES
2020
SAY
1. Observe the
figure given below: (2)
Fill in the blanks a, b, c, d in the figure. (Hint: a, b, c –
stages, d – enzyme).
ü Answer:
(a) Denaturation
(b) Annealing
(c) Extension
(d) Taq polymerase
2. EcoRI is a
restriction endonuclease. What do E, Co, R, I represent? (2)
ü Answer:
E = Escherichia (Genus name of bacteria)
Co = Coli (Species name of bacteria)
R = Strain
I = First extracted enzyme (Order of extraction).
2020
MARCH
1. Which among the
following is a selectable marker in pBR - 322? (1)
a.
"Ori"
b. Hind III
c.
ampR
d. rop
ü Answer:
(c) ampR
2. How can we make
a host cell competent to receive a foreign gene or DNA? (2)
ü Answer:
Treating the cells with specific concentration of a
divalent cation such as calcium.
Incubating the cells with recombinant DNA on ice. Place
them briefly at 420C (heat shock). Again, place them back on ice.
3. The following
are the diagrams of two important processes used in rDNA technology. (3)
a. Identify A and
B.
b. Write the uses
of A and B in rDNA technology.
ü Answer:
(a) A= Polymerase Chain Reaction (PCR)
B= Gel electrophoresis.
(b) PCR is used for the amplification of gene of
interest.
Gel
electrophoresis is used to separate DNA fragments of different sizes.
2019
SAY June
1. Restriction
endonuclease recognises a
specific sequence in the DNA. Name that sequence and write its peculiarity. (2)
ü Answer:
Palindromic nucleotide sequence.
Peculiarity: It is a sequence of base pairs that read the same on
the two strands in 5' → 3' direction and in 3' → 5' direction.
2. Match the items
of column A with B: (2)
|
A |
B |
|
(a) Cloning Vector (b) Separation of DNA fragments (c) PCR (d) Converts raw materials into specific products |
(i) Bioreactor (ii) Taq polymerase (iii) Electrophoresis (iv) Hind 11 (v) pBR322 |
ü Answer:
|
A |
B |
|
(a) Cloning Vector (b) Separation of DNA fragments (c) PCR (d) Converts raw materials into specific products |
(v) pBR322 (iii) Electrophoresis (ii) Taq polymerase (i) Bioreactor |
2019
MARCH
1. What is the
function of Restriction Endonuclease in recombinant DNA technology? (1)
a. Link together
fragments of DNA
b. Make millions
of copies of DNA
c. Cut DNA into
many fragments.
d. Separate
fragments of DNA
ü Answer:
(c) Cut DNA into many fragments
2. Recombinant DNA
technology is a complex process which involves several steps. Write down the
major steps in recombinant DNA technology. (3)
ü Answer:
1. Isolation of the Genetic Material (DNA).
2. Cutting of DNA by restriction enzymes.
3. Amplification of Gene of Interest using PCR.
4. Insertion of Recombinant DNA into Host Cell.
5. Obtaining the Foreign Gene Product.
6. Downstream Processing.
3. The discovery
of Restriction Endonuclease is considered as "milestone" in
the history of genetic engineering. (3)
a. Which is the
first discovered restriction endonuclease?
b. What are the
criteria for naming of restriction endonuclease?
ü Answer:
(a) Hind II.
(b) First capital letter: Genus name.
Second two letters: Species name.
Fourth letter: Strain of bacterium from which the enzyme
is isolated.
Roman number: Order of isolation of enzyme.
2018
SAY June
1. 'In Gel
electrophoresis, the separated DNA fragments can be visualized after staining.
Name the stain used for it. (1)
ü Answer:
Ethidium bromide.
2. Multiple copies
of gene of interest can be synthesised in vitro. Name the technique and its
requirements. (2)
ü Answer:
Polymerase Chain Reaction (PCR).
Requirements: Primase, Taq polymerase, Target
DNA etc.
3. Restriction
endonuclease enzymes are used to cut the DNA at specific sequence. (3)
a.
Write the name
of first isolated one.
b.
Write the
convention for naming these enzymes.
ü Answer:
(a) Hind II
(b) First capital letter: Genus name.
Second two letters: Species name.
Fourth letter: Strain of bacterium from which the enzyme
is isolated.
Roman number: Order of isolation of enzyme.
2018
MARCH
1. The DNA
fragments can be separated using gel electrophoresis. (2)
a. Name the gel
used in this technique.
b. Write the name
of technique used to remove the DNA from the gel.
ü Answer:
(a) Agarose
gel.
(b) Elution.
2. Observe the
following figure. (2)
a. Identify the
figure.
b. What does (i)
tetR (ii) rop (iii) ori denote?
ü Answer:
(a) pBR322 (E. coli cloning vector).
(b) (i) Tetracycline resistance gene
(ii) Gene that codes for the proteins involved in the
replication of plasmid.
(iii) Origin of replication.