Biology Today — December 2017
- How is gene therapy being used in treating ADA deficient
patients?
- What are bioreactors? List five growth conditions that a
bioreactor provides for obtaining the desired product.
- Differentiate between type I, II and III restriction
endonucleases.
- (a) Name the bacterium which produces Bt toxin. What is
the significance of this toxin?
(b) Name the gene which codes for this toxin. Why this
toxin does not kill the bacterium?
(c) Name the genes that prevent infection by cotton
bollworms and corn borers in pest resistant plants.
- Explain molecular farming or molecular harvesting.
- Name and explain the technique used in the separation and
isolation of DNA fragments to be used in recombinant DNA
technology.
- (a) What do you mean by the term biopiracy?
(b) What measures are being taken by the Indian
Government to prevent biopiracy?
- What are the basic requirements of a polymerase chain
reaction?
OR
How Agrobacterium tumefaciens has been made a useful
cloning vector to transfer DNA to plant cells?
- (a) How is mature insulin different from proinsulin secreted
by pancreas in humans?
(b) How human functional insulin is produced using rDNA
technology?
(c) Why is the functional insulin thus produced,
considered better than the ones used earlier by
diabetic patients?
- DNA being hydrophilic cannot pass through the cell
membranes of a host cell. Explain how does recombinant
DNA get introduced into the host cell to transform the latter.
- Explain the process of RNA interference.
SECTION - D
- Neeraj was having a debate with Mohit regarding the
advantages and disadvantages of transgenic animals.
Neeraj was of the view that production of transgenic
animals violates the integrity of species and animals suffer
from cruelty so, it is unethical. On the other hand, Mohit
emphasised the benefits that transgenic animals provide to
the human race in various fields especially medicine.
(a) How do transgenic animals benefit humans?
(b) List the ethical issues related with the production of
transgenic animals.
(c) What values are shown by Neeraj and Mohit?
SECTION - E
- What is cloning vector? Why is it used? Explain the
technique of using such a vector in E.coli.
OR
Describe the process of recombinant DNA technology with
the help of a neatly labelled diagram.
- A desired gene was identified in an organism for some
experiments. Explain the processes that should be used for
(a) cutting this desired gene at specific locations.
(b) synthesis of multiple copies of this desired gene.
OR
(a) Briefly explain the principle and the role of ELISA.
(b) How transgenic animals proved to be beneficial in:
(i) Production of biological products
(ii) Chemical safety testing?
(c) Diagrammatically show synthesis of cDNA from RNA.
- (a) How recombinant DNA technology helps in detecting
the presence of mutated gene in cancer patients?
(b) Explain any three methods to force ‘alien’ or
recombinant DNA into host cells.
OR
(a) List five advantages of using genetically modified
plants over conventional ones. What are the health
risks on humans by GM plants?
(b) Describe the responsibility of GEAC, set up by the
Indian Government.
SOLUTIONS
- Kary Mullis developed the technique Polymerase Chain
Reaction (PCR). The objective of this technique is selective
amplification of specific region of DNA molecule.
- In gel electrophoresis, ethidium bromide (EtBr) is used to
stain separated DNA fragments so that it can be seen as
bright orange coloured bands after exposure to UV radiation.
- The milk produced by transgenic cow Rosie, is enriched with
the human protein alpha lactalbumin and is nutritionally
more balanced product for human babies than natural cow
milk.
- DNA is a negatively charged molecule and during gel
electrophoresis, DNA fragments move towards anode
(positive electrode) under the influence of electrical field.
- Golden rice is a transgenic variety of rice that contains good
quantities of b-carotene, a principle source of vitamin A.
- (a) Differences between action of exonucleases and
endonucleases are as follows :
