Navodaya Vidyalaya Samiti – Bhopal Region.
CHAPTER 11
BIOTECHNOLOGY: PRINCIPLES AND PROCESSES
 Two core techniques that enabled birth of modern biotechnology:
 Genetic engineering: Techniques to alter the chemistry of genetic material (DNA
and RNA) to introduce into host organisms and thus change the phenotype of the
host organism.
 Maintenance of sterile (microbial contamination-free) ambient chemical
engineering processes to enable growth of only the desired microbe/eukaryotic
cell in large quantities.
Conceptual development of the principle of genetic engineering:
 Asexual reproduction preserves the genetic identity of species.
 Sexual reproduction creates variation and creates unique combinations of genetic
makeup.
 Traditional hybridization procedures used in plant and animal breeding lead to inclusion
of undesirable genes along with desired genes.
 The techniques of genetic engineering which includes creation of recombinant DNA, use
of gene cloning and gene transfer, overcome this limitation and allows us to isolate and
introduce only one or a set of desirable genes without introducing undesirable genes into
target organism
 Three basic steps in genetically modifying an organism –
 Identification of DNA with desirable gene
 Introduction of the identified DNA into the host.
 Maintenance of introduced DNA in the host and transfer of the DNA to its
progeny.
TOOLS OF RECOMBINANT DNA TECHNOLOGY:
Restriction Enzymes:
 In the year 1963 two enzymes discovered from Escherichia coli which restrict the growth
of bacteriophage in it.
 One of these added methyl groups to DNA.
 Other cut the phage DNA. (restriction endonuclease)
 The first restriction endonuclease discovered is Hind II.
 Hind II always cut DNA molecule at particular point by recognizing a specific sequence
of six base pairs. This is called recognition sequence for Hind II.
 Till date around 900 restriction enzymes isolated from 200 strains of bacteria each of
which recognize different recognition sequences.
 Restriction enzyme belongs to nucleases.
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 There are two kind of nucleases:
 Exonuclease
 Endonuclease
 Exonuclease removes nucleotides from the free ends of the DNA.
 Endonucleases make cuts at specific positions within the DNA.
 Each restriction endonuclease recognizes a specific palindromic nucleotide sequences in
the DNA.
 Palindromes are the group of letters that read same both forward and backward, e.g.
“MALAYALAM”.
 The palindrome in DNA is a sequence of base pairs that reads same on the two strands
when orientation of reading is kept same.
 The restriction enzyme cut the strand of DNA little away from the centre of the
palindrome sites, but between the same two bases on the opposite strand. This leaves
single stranded portions at the ends. There are overhanging stretches called sticky ends on
each strand.
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 This stickiness of the ends facilitates the action of the enzyme DNA ligases.
 The foreign DNA and the host DNA cut by the same restriction endonuclease, the
resultant DNA fragments have the same kind of ‘sticky-ends’ and these can be joined
together using DNA ligases.
Convention for naming restriction endonuclease:
 The first letter of the name comes from the genus.
 Second two letters come from the species of the prokaryotic cell from which the
enzyme isolated
 The fourth letter is in capital form derived from the Strain of microbes.
 The Roman letter followed is the order of discovery
 Best example: EcoRI comes from Escherichia coli RY 13
Separation and isolation of DNA fragments:
 The cutting of DNA by restriction endonucleases results in the fragments of DNA.
 These fragments are separated by a technique called gel electrophoresis.
Gel electrophoresis instrument.
 Since the DNA fragments are negatively charged, they can be separated by forcing them
to move towards anode under an electric field through a medium/matrix.
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 Most commonly used matrix is agarose, a natural polymer extracted from sea weed.
 DNA fragments separate according to their size through sieving effect provided by the
agarose gel. Hence the smaller the fragment size, farther it moves.
+ + + + + + + + + + + + +
4/11/2012
H. K. GIRI. PGT (BIO) JNV
DHENKANAL
48
_ _ _ _ _ _ _ _ _ _ _ _
Sieving effect of gel
 The separated fragments are visualized by staining them with Ethidium bromide followed
by exposure to UV radiation.
 The separated bands of DNA are cut out from the agarose gel and extracted from the gel
piece. This step is called elution.
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Cloning vectors:
 The plasmid and bacteriophages have the ability to replicate
within bacterial cells independent of the control of
chromosomal DNA.
 Alien DNA linked with the vector multiply its number equal to
the copy number of the plasmid or bacteriophage.
Features of cloning vector:
Origin of replication:
 This is the sequence where the replication starts called ori gene.
 The alien DNA linked with vector also replicates.
 Controls the copy number of the linked DNA.
Selectable marker:
 It is required to identify recombinant from the
non-recombinant.
 Helps in identifying and eliminating nontransformants and selectively permitting the
growth of the transformants.
 Transformation is a procedure through which a
piece of foreign DNA is introduced in a host
bacterium.
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 Normally, the gene coding resistance to antibiotics such as ampicilin. Tetracycline,
chloramphenicol or kanamycins etc are considered as useful selectable markers for
E.coli.
 The normal E.coli cells do not carry resistance against any of antibiotics.
Cloning sites:
 In order to link the alien DNA, the vector needs to have very few, preferably single,
recognition sites (palindromic site) for the commonly used restriction endonuclease.
 Commonly used vector is pBR322, for E.coli.
 The ligation of foreign DNA is carried out at a restriction site present in one of the
two antibiotic resistance genes.
 If a foreign DNA ligated or inserted at the Bam H I site of tetracycline resistance gene
in the vector pBR322, the recombinant plasmid will lose tetracycline resistance.
(insertional inactivation)
 The recombinant can be identified from the non-recombinant in following steps:
 All are grown in ampicillin medium
 One replica of above plate grown in ampicilin medium (control)
 Other replica grown in the medium containing both tetracycline and
ampicillin.
 The colonies grows in plate-I but failed to grow in plate-II are identified as
recombinants.
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Alternative selectable marker:
 In E.coli a plasmid called PUK-18
is used as selectable marker, which
is better than pBR322.
 The foreign DNA is introduced
within the coding sequence of an
enzyme β-galactosidase, which
convert X-Gal (chromatogenic
substrate) into Galactose and 5bromo+4 chloroindigo (blue color)
 The non-recombinant produce
enzyme and give blue colored
colonies.
 The recombinant unable to produce β-galactosidase and does not produce blue
colored colonies after addition of chromatogenic substrate i.e. X-Gal.

This inactivation of insertion of foreign DNA called insertional
inactivation.
Vectors for cloning genes in plants and animals:
 Agrobacterium
tumefaciens,
a
pathogenic bacterium of several
dicot plants.
 This bacterium contains a plasmid
called Ti-plasmid.(tumor inducing)
 In
natural
condition
the
A.tumifaciens transfer the T-DNA
into the plant which transform
normal plant cells into a tumor and
direct these tumor cells to produce
the chemical required by the
pathogen.
 Retroviruses in animals have the ability to transform normal cells into cancerous
cells.
 The dis-armed retroviruses are being used to transfer gene into animals.
 In Ti-plasmid the T-DNA is replaced by the gene of interest, still A.tumifaciens able
to transfer the gene into the plant without causing tumor in plants.
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Competent Host (for transformation with recombinant DNA)
 DNA is a hydrophilic molecule; it cannot pass through cell membranes.
 In order to force bacteria to take up the plasmid, the bacterial cells must first be made
‘competent’ to take up DNA.
 The bacterial cell is treated with divalent cation such as calcium, which increases the
efficiency of DNA up take by the bacteria.
 Recombinant DNA and the bacterial cells are incubated in ice, followed by placing them
briefly at 42oC (heat shock) and then putting them back in ice.
 By microinjection the recombinant DNA directly injected into the nucleus of the animal
cell.
Microinjection of genetic material
 Plant cells are bombarded with high velocity micro-particles of gold or tungsten coated
with DNA in a method known as biolistics or gene gun.
Gene gun or biolistics
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 The disarmed pathogen vectors which when allowed infecting the cell transfer the
recombinant DNA into the host.
PROCESS OF RECOMBINANT TECHNOLOGY:







Isolation of DNA ,
Fragmentation of DNA by restriction endonuclease.
Isolation of desired DNA fragment by gel electrophoresis.
Ligation of DNA fragment with a vector by DNA ligase
Transferring the recombinant DNA into the host
Culturing the host cells in a medium at large scale in a bioreactor.
Extraction of desired product by downstream processing.
Isolation of the Genetic material (DNA):







Bacterial cell wall digested by Lysozyme.
Plant cell wall is digested by cellulase and pectinase.
Fungal cell wall is digested by chitinase.
RNA of the cellular content is digested by ribonuclease.
Proteins are removed by Proteases.
Purified DNA ultimately precipitated out after addition of chilled ethanol.
The precipitated DNA is separated and removed by spooling.
Amplification of Gene of Interest using PCR:
 PCR stands for Polymerase chain reaction:
 Multiple copy of gene of interest can be synthesized in vitro.

PCR includes following steps:
Denaturation:
 Double stranded DNA made single stranded.
 It is done by heating the DNA at 94oC.
 Each single stranded DNA is called Template strand.
Annealing:
 Two sets of primer (small oligonucleotide chain that are complementary to the DNA
at 3’ end of the DNA template) added to the medium.
 This is done at around 50oC.
Extension:
 Deoxyribonucleotides triphosphates are added in the medium.
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 Taq polymerase catalyses the polymerization reaction using nucleotides extending
from the primer towards 5’ end of the template.
 Taq polymerase is a thermostable polymerase isolated from a bacterium called
Thermus aquaticus.
 It catalyses polymerization reaction at 74oC.
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Obtaining the Foreign Gene product or Recombinant product:
 The protein encoding gene is expressed in a heterogeneous host is called a recombinant
protein.
 The host is cultured in a continuous culture system provided in bioreactor.
 A bioreactor provides optimum growth conditions (temperature, pH, substrate, salts,
vitamins, oxygen)
 Bioreactor covert the raw materials into specific product, specific enzyme.
Downstream processing:
 After biosynthesis inside the bioreactor, the product has to be subjected through a series
of processes before it is ready for marketing.
 The process includes separation and purification, which are collectively referred as
downstream processing.
 The product has to be formulated in suitable preservatives.
 Such formulation has to undergo through clinical trials as in case of drugs.
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QUESTIONS
CHAPTER-11
BIOTECHNOLOGY: PRINCIPLES AND PROCESSES
VERY SHORT ANSWER TYPE QUESTION (1 MARK)
1. What you call to the specific DNA sequence, which initiates the process of replication?
2. Define a plasmid.
3. Name the first restriction endonuclease isolated from the bacteria.
4. You are working with a plasmid (here) that has two antibiotic resistance genes for
tetracycline (tetr) and ampicillin (ampr) with a BamHI restriction site within the tetr gene.
You restrict a mixture of foreign DNA and your plasmid with BamHI, use ligase to create
recombinant molecules, and transform E. coli sensitive to both antibiotics with the
mixture. You then spread the E. coli onto plates with four types of media: (1) without any
antibiotic, (2) with just tetracycline, (3) with just ampicillin, or (4) with both antibiotics.
The bacteria with the recombinant plasmid would grow on_______________?
5. What you call to the specific recognition site of a restriction endonuclease?
6. After action of a restriction endonuclease there is presence of overhanging stretches.
What you call to such stretches? What is its significance?
7. Name the popularly used stain used to visualize the DNA fragment in gel electrophoresis.
8. This figure shows the first two steps in synthesizing complementary DNA. The enzyme
shown as a yellow sphere is _______, and the purpose of the oligo dT (TTTT) is to serve
as a _______.
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9. What you call to the sequence of DNA where replication starts?
10. You want to introduce a transgene at tetracycline resistance gene of a plasmid called
pBR322. Name the restriction enzyme you will use for a successful transformation.
11. Name two antibiotic resistance genes present in the plasmid called pBR322, which are
used, as selectable marker in gene transfer technology.
12. You have transferred an alien DNA within the coding sequence of a-galactosidase. For
selection of transformant you have added a chromatogenic substrate, still it gives blue
color. What does it mean?
13. Name the gene transferred from Agrobacterium tumifaciens into a dicot plant, which
induce tumor.
14. Identify the restriction enzyme for the given palindromic site.
15. Which plasmid of the Agrobacterium tumifaciens has been manipulated to transfer a
desirable foreign DNA into dicot plant?
16. Name the group of virus that induces cancer in human being.
17. Why the DNA cannot pass through the cell membrane?
18. You want to extract the DNA from a fungal cell. Which enzyme will be suitable for that
purpose?
19. What is the role of cellulase in the process of genetic engineering?
20. What you call to the process by which multiple copies of gene (or DNA) of interest are
synthesized in vitro?
21. Name the specific DNA polymerase used in the PCR.
22. Name the bacterium from which the Taq polymerase is being extracted.
23. Name the substance used as a medium in gel electrophoresis.
24. What is Bioconversion?
25. Which enzymes are known as “molecular Scissors”?
26. Why does DNA moves towards anode in gel electrophoresis.
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27. Name the commonly used vector for trans formation in plant cell?
28. Name the technique used for amplification of DNA?
29. Name the enzyme responsible for removal of 5’ – phosphate group from nucleic acid?
30. Who isolated Restriction enzymes for the first time?
31. Why do eukaryotic cells do not contain restriction enzymes?
SHORT ANSWER TYPE QUESTION (2 MARK)
1. How genetic engineering is advantageous than traditional hybridization in plant and
animal?
2. Write at least four characteristic features of the given cling vector.
3. Distinguish between exonuclease and endonuclease.
4. What is palindromic site in a DNA? Give one example of such site in a DNA. Write the
name of the restriction enzyme that acts on that particular site.
5. What do you mean by the word Vector in relation to the recombinant DNA technology?
Give one example of commonly used vector in this technology.
6. Why is it necessary to cut both the foreign DNA and the vector DNA by same restriction
enzyme? Give one specific example.
7. Describe the principle in which the gel-electrophoresis works?
8. What do you mean by the term elution in relation to the gel electrophoresis?
9. You have transferred an alien DNA into a plasmid. How could you known whether the
Alien DNA successfully transferred into the plasmid?
10. Explain with a suitable example, how a chromatogenic substrate is used for identification
of a transformants in the principle of insertional inactivation?
11. How the Agrobacterium tumefaciens induce tumor in dicot plant? How the bacterium
benefited by inducing tumor in dicot plant?
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12. Describe how retrovirus is used to transfer a desirable gene into human?
13. What are the principal steps in the process of recombinant DNA technology?
14. What do you mean by Taq polymerase? What is its significance in PCR?
15. How the recipient host cells made competent to receive an rDNA?
16. What do you mean by a recombinant protein? Site one example of such protein.
17. What do you mean by bioreactor? How it is useful in genetic engineering?
18. Write any two properties of restriction endonuclease enzymes?
19. What is ‘Selectable marker’? What is their use in genetic engineering?
20. How can the desired product formed after genetic engineering are produced on a
commercial scale?
21. What is “Insertional Inactivation”?
22. What are the two basic techniques involved in modern Biotechnology?
23. Represent diagrammatically the E. coli. Cloning vector pBR 322.
24. Differentiate between plasmid DNA and chromosomal DNA?
25. What is the role of enzyme “Ligase” in genetic Engineering?
26. Name the components a bioreactor must possess to achieve the desired product?
27. The
following
proteins
of
given
molecular
weight
are
Subjected
to
Gel
electrophoresis. Write the order of Sequence in which these proteins are isolated in a gel?
28. How is gene Z used as a marker?
29. While doing a PCR, ‘denaturation’ step is missed. What will be its effect on the process?
30. Explain how the bacterial DNA gets protected against phage which described in diagram
below.
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31. Name a recombinant vaccine that is currently being used in vaccination program.
32. Do biomolecules (DNA, protein) exhibit biological activity in anhydrous conditions?
33. What modification is done on the Ti plasmid of Agrobacterium tumefaciens to convert it
into a cloning vector?
34. Match the column A with column B
Column – A
Column – B
(i) Bacterial proteins that have the ability to cut both (a) recombinant DNA
Strands of the DNA molecule at certain points
(ii)
Contain foreign DNA
(b) vector
(iii)
Is made by connecting segments of DNA
(c)restriction enzymes
From different sources
(iv)
General term for a vehicle used to transfer
(d) plasmid
A foreign DNA fragment into a host cell
(v)
A small ring of DNA found in a bacterial cell
(e)transgenic organisms
(vi)
The procedure for cleaving DNA from an
(f) genetic engineering
Organism into small segments, and inserting or recombinant DNA
The segments into another organism
technology
35. What is Bioreactor? What are the advantages of Stirred tank Bioreactor over Shake
flask? Show diagrammatically a simple Stirred tank Bioreactor?
36. How is copy number of the plasmid vector related to yield of recombinant protein?
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37. Would you choose an exonuclease while producing a recombinant DNA molecule? What
does H in’‘d’ and ‘III’ refer to in the enzyme Hind III?
38. Restriction enzymes should not have more than one site of action in the cloning site of a
vector. Comment.
39. What does ‘competent’ refer to in competent cells used in transformation experiments?
40. What is the significance of adding proteases at the time of isolation of genetic material
(DNA)?
SHORT ANSWER TYPE QUESTION (3 MARKS)
1. What are the three basic steps required for genetically modifying an organism?
2. Name the process by which the digested DNA fragments get separated according to their
size. Describe the process briefly.
3. What do you mean by cloning vector? Name two commonly used cloning vector in
recombinant DNA technology.
4. What is insertional inactivation? Describe it with suitable example.
5. Describe different method for transfer of an alien DNA into the host cell.
6. Describe briefly how the genetic material can be isolated in pure form from a plant cell?
7. Describe briefly the process of polymerase chain reaction. What is its significance?
8. Mention the important properties which a good vector must possess?
9. Describe any three vectors less method of introducing the rRNA into a competent host
cell?
10. Why Agrobacterium is mediated genetic transformation described as Natural Genetic
engineering in plants?
11. Mention the important tools required for genetic engineering technology?
12. What is meant by gene cloning?
13. Both a wine maker and a molecular biologist that had developed a recombinant vaccine
claim to be biotechnologists. Who in your opinion is correct?
14. Restriction enzymes that are used in the construction of recombinant DNA are
endonucleases which cut the DNA at ‘specific-recognition sequence’. What would be the
disadvantage if they do not cut the DNA at specific-recognition sequence?
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15. A plasmid DNA and a linear DNA (both are of the same size) have one site for a
restriction endonuclease. When cut and separated on agarose gel electrophoresis, plasmid
shows one DNA band while linear DNA shows two fragments. Explain.
16. A mixture of fragmented DNA was electrophoreses in an agarose gel. After staining the
gel with ethidium bromide, no DNA bands were observed. What could be the
reason?
17. Describe the role of CaCl2 in the preparation of competent cells?
LONG ANSWER TYPE QUESTIONS (5 MARKS)
1. Describe briefly the features that required facilitating cloning into a vector.
2. Describe the various steps involved in Recombinant DNA technology with the help of a
well labeled. Diagram?
3. Expand PCR? Describe the different Steps involved in this technique?
4. What is Restriction enzyme? Why do bacteria have these restriction enzymes? Show
diagrammatically a restriction enzyme its recognition & the product it produces?
5. For selection of recombinants, insertional inactivation of antibiotic marker has been done
by insertional inactivation of a marker gene coding for a chormatogenic substrate. Give
reasons.
6. Describe the role of Agrobacterium tumefaciens in transforming a plant cell.
7. Illustrate the design of a bioreactor. Highlight the difference between a flask in your
laboratory and a bioreactor which allows cells to grow in a continuous culture system.
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QUESTIONS FROM PREVIOUS YEARS BOARD PAPERS:
CHAPTER-11
BIOTECHNOLOGY: PRINCIPLE AND PROCESSES
VERY SHORT ANSWER TYPE QUESTION (1 MARK)
1. Name a technique by which multiple copy of a piece of DNA can be made.
(FOREIGN 2003)
2. Explain the contribution of the Thermus aquaticus in the amplification of a gene of
interest.
(DELHI 2009)
3. A plasmid and a DNA sequence in a cell need to be cut for producing recombinant DNA.
Name the enzyme which acts as molecular scissors to cut the DNA segments. (CBSESP)
4. How is the action of exonuclease different from that of endonuclease? (A.I.CBSE 2010)
(CBSE – SP)
5. In plants, how is alien DNA introduced into the host cell?
6. Why is the enzyme cellulase used for isolating genetic material from plant cells but not
for animal cells?
(DELHI 2010)
7. What is the host called that produces a foreign gene product? What is this product called?
(FOREIGN 2010)
8. How can the bacterial DNA be released from the bacterial cell for biotechnology
experiments?
(DELHI 2011)
9. Mention the uses of cloning vector in biotechnology.
(DELHI 2011)
10. Biotechnologists refer to Agrobacterium tumefaciens as a natural genetic engineer of
plants. Give reasons to support the statement.
(A.I.CBSE 2011)
11. Why is it essential to have a ‘selectable marker’ in a cloning vector?
(A.I.CBSE 2011)
SHORT ANSWER TYPE QUESTION (2 MARK)
1. Differentiate between gene therapy and gene cloning.
(FOREIGN 2002)
2. How a transgenic organism does differ from the rest of its population? Site any two
examples of such organisms for human advantage?
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3. What is Ti plasmid? Name the organism where it is found. How does it help in genetic
engineering?
(A.I.CBSE 2002)
4. Explain any two methods of vector less gene transfer.
(DELHI 2002)
5. Differentiate between rDNA and cDNA.
(DELHI 2003)
6. Define genetic engineering. Name one natural genetic engineer of plants (DELHI 2003)
7. Do eukaryotic cells have restriction endonuclease? Justify your answer.
(DELHI 2007)
8. How DNA segments can separated by gel electrophoresis, be visualized and isolated?
(A.I.CBSE 2008)
9. What are recombinant proteins? How do bioreactors help in their production?
(A.I.CBSE 2009)
10. How is DNA isolated in purified form from a bacterial cell?
(A.I.CBSE 2009)
11. Explain the contribution of Thermus aquaticus in the amplification of a gene of interest.
(FOREIGN 2009)
12. What are recombinant proteins? How do bioreactors help in their productions?
(DELHI 2009)
13. A recombinant DNA is formed when sticky ends of vector DNA and foreign DNA join.
Explain how the sticky ends are formed and get joined?
A.I.CBSE 2010)
14. Answer the following questions:
a. Mention the number of primers required in each cycle of polymerase chain
reaction (PCR). Write the role of primers and DNA polymerase in PCR.
b. Give the characteristic feature and source organism of the DNA polymerases used
in PCR.
A.I.CBSE 2010)
15. A recombinant DNA is formed when sticky ends of vector DNA and foreign DNA join.
Explain how the sticky ends are formed and get joined.
(A.I.CBSE 2010)
16. Provide one word or one sentence information about ‘plasmid’ with respect to its
(a)
Chemical nature
(b)
Its duplication.
(CBSE – SP)
17. Expand the following:
a. PCR
(CBSE – SP)
b. Bt
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18. Answer the following questions:
(a)
Illustrate the recognition sequence of EcoRI and mention what such sequences are
called?
(b)
(A.I.CBSE 2010)
How does restriction endonuclease act on a DNA molecule?
19. A and B are the two different cloning vectors in two different bacterial colonies cultured
in chromogenic substrate. Bacteria colonies with cloning vector A were colorless
whereas those with B were blue coloured. Explain giving reasons the cause of the
difference in colour that appeared.
(A.I.CBSE 2010 C)
20. Any recombinant DNA with a desired gene is required in billion copies for commercial
use. How is this amplification done? Explain.
(DELHI 2010 C)
21. How did Eli Lily synthesize the human insulin? Mention one difference between insulin
and the one synthesized by the human pancreas.
(DELHI 2010 C)
22. Explain the action of the restriction endonuclease EcoRI.
(FOREIGN 2010)
23. Why is ‘origin of replication’ (ORI) required to facilitate cloning into vector?
(FOREIGN 2010)
24. How are DNA fragments separated by gel electrophoresis visualized and separated for
use in constructing recombinant DNA?
(FOREIGN 2010)
25. A schematic representation of polymerase chain reaction (PCR) up to extension stage is
given below. Answer the questions that follow:
(a) Name the process ‘a’.
(b) Identify ‘b’.
(c) Identify ‘c’ and mention its importance in PCR.
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26. Name the type of bioreactor shown. Write the purpose for which it is used.
27. List the key tools used in recombinant DNA technology.
(DELHI 2011)
28. Explain the role of Ti plasmids in biotechnology.
(DELHI 2011)
29. How are recombinant vectors created? Why is only one type of restriction endonuclease
required for creating one recombinant vector?
(FOREIGN 2011)
30. Name the organism from where the thermostable DNA polymerase is isolated. State its
role in genetic engineering.
(FOREIGN 2011)
31. Study the diagram below and answer the following questions:
a. Why DNA fragments in band ‘D’ moved farther way in comparison to ‘C’?
b. Identify the anode end in the diagram.
c. How are these DNA fragments visualized?
(FOREIGN 2011)
32. Answer the following questions:
a. Why are restriction endonucleases known as molecular scissors?
b. Write the convention used for naming such enzymes.
(FOREIGN 2011)
33. Answer the following questions:
a. A recombinant vector (plasmid) with a gene of interest inserted within the gene of
β-galactosidase enzyme is introduced into a bacterium. Explain the method that
would help in selection of recombinant colonies from non-recombinant one
(A.I.CBSE 2012)
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b. Why is this method of selection referred to as “insertional inactivation?
34. Name the source organism that possesses Taq polymerase. What is so special about the
function of this enzyme?
(A.I.CBSE 2012)
35. Explain the work carried out by Cohen and Boyer that contributed immensely to
biotechnology.
(DELHI 2012)
36. How can the following be made possible for biotechnology experiments?
a. Isolation of DNA from bacterial cell.
(FOREIGN 2012)
b. Reintroduction of the recombinant DNA into the bacterial cell.
37. Name the source of the DNA polymerase used in PCR technique. Mention why it is
used?
(A.I.CBSE 2013)
38. Write any four ways used to introduce a desired DNA segment into a bacterial cell in
recombinant technology experiments.
(A.I.CBSE 2013)
SHORT ANSWER TYPE QUESTION (3 MARKS)
1. Why Agrobacterium mediated genetic transformation described as natural genetic
engineering in plants?
(DELHI 2002C)
2. What is genetic engineering? List the steps involved in rDNA technology. (DELHI
2002C)
3. Why are cloning vectors necessary in cloning? Name any two such vectors that are used
in experiments with Escherichia coli.
(FOREIGN 2003)
4. Answer the following questions:
5. What are “molecular scissor”? Give one example.
6. Explain their role in recombinant DNA technology.
(DELHI 2008)
7. DNA being hydrophilic cannot pass through the cell membrane of a host cell. Explain
how recombinant DNA get introduces into host cell to transform the later.(DELHI 2008)
8. Name the technique to obtain multiple copies of a DNA segment of interest, synthesized
in vitro. Name two sets of primers that are necessary for reaction to occur. Mention three
diagnostic applications of this technique.
(DELHI 2008)
9. Explain any three methods to force ‘alien’ or recombinant DNA into the host cells.
(DELHI 2008)
10. Why is Agro bacterium tumefaciens a good cloning vector? Explain.
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11. What is a recombinant DNA? List its features. How do enzymes restriction endonuclease
and DNA ligase help its formation?
(A.I.CBSE 2008 C)
12. Explain the importance of (a) ori, (b) ampR and (c) rop in the E.coli vector pBR322
shown below.
(A.I.CBSE 2008)
a.
13. How the bacterium Thernmus aquaticus employed in recombinant DNA technology?
(A.I.CBSE 2008)
14. A vector is engineered with three features which facilitate its cloning within the host cell.
List the three features and explain each one of them.
(FOREIGN 2008)
15. Why are restriction endonucleases so called? Explain their role as ‘molecular scissors’ in
recombinant DNA technology.
(FOREIGN 2008)
16. Name the source of organism from which Ti plasmid is isolated. Explain the use of this
plasmid in biotechnology.
(FOREIGN 2009)
17. Name and explain the techniques used in the separation and isolation of DNA fragments
to be used in recombinant DNA technology.
(A.I.CBSE 2009)
18. Answer the following questions:
iii.
i.
What is EcoRI? What does ‘R’ represent in this?
ii.
Give the palindromic nucleotide sequence recognize by it.
Explain its action.
(FOREIGN 2009)
19. Answer the following questions:
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20.
21. Identify the selectable markers in the diagram of E.coli vector shown above.
22. How is the coding sequence of α-galactosidase considered as a better marker than the one
identified by you in the diagram? Explain.
(DELHI 2009)
23. Name the insect pest that killed by the products of cry IAc gene. Explain how the gene
makes the plant resistant to the insect pest.
(A.I.CBSE 2010)
24. Explain the process by which a bacterial cell can be made ‘competent’. Why is it
essential to make bacterial cells ‘competent’ in recombinant DNA technology?
(FOREIGN 2010)
25. Answer the following questions:
26.
27. Name ‘a’ DNA and ‘b’ DNA
28. Name the restriction enzyme that recognizes this palindrome
29. Name the enzyme that can link these two DNA fragments.
(CBSE – SP)
30. Explain with reference to PCR.
31. A specific enzyme helps in amplification in PCR. Name the bacterium from which it is
isolated and state how its thermostable nature is helpful.
32. Explain its use in molecular diagnosis.
(CBSE - SP)
33. Name the particular technique in Biotechnology whose steps are shown in the figure, Use
the figure to summarize the technique in three steps.
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34. An interesting property of restriction enzymes is molecular cutting and pasting.
Restriction enzymes typically recognize a symmetrical sequence of DNA.
Notice that the top strand is the same as the bottom strand, but reads backward. When the
enzyme cuts the strand between G and A, it leaves overhanging chains:
(a)
What is this symmetrical sequence of DNA known as?
(b)
What is the significance of these overhanging chains?
(c)
Name the restriction enzyme that cuts the strand between G and A.
(CBSE-SP)
39. A policeman finds a very small piece of body tissue from the site of a crime and takes it
to the forensic department.
40. By which technique will they amplify the DNA collected from the tissue sample?
41. Mention in a sequence, the 3 steps involved in each cycle of this technique;
42. What is the role of thermostable DNA polymerase in this technique? (CBSE-SP)
43. Describe the different steps carried out in Polymerase Chain Reaction (PCR). State any
two applications of PCR in medical sciences.
(A.I.CBSE 2010C)
44. Answer the following questions:
45. EcoRI is a restriction endonuclease. How is it named so? Explain.
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46. Write the sequence of DNA bases that the enzyme recognizes. Mention the point at
which the enzyme makes a cut in the DNA segment.
(DELHI 2010 C)
47. Write the term given to A and C and why?
48. Expand PCR. Mention is importance in biotechnology.
(DELHI 2011)
49. How is the amplification of a gene sample of interest carried out using Polymerase Chain
Reaction (PCR)?
(A.I.CBSE 2012)
50. Draw a schematic diagram of pBR 322 plasmid and label the following in it:
(a)
Any two restriction sites
(b)
Ori and rop genes.
(DELHI 2012)
51. How the DNA fragments are separated andisolated for DNA fingerprinting? Explain.
(FOREIGN 2012)
LONG ANSWER TYPE QUESTIONS (5 MARKS)
1. What is rDNA? Explain the technique of cloning rDNA.
(A.I.CBSE 2002)
2. What is cloning vector? Explain the technique of using a vector in E.coli. (DELHI 2008)
3. Answer the following questions:
4. Mention the role of vectors in recombinant DNA technology. Give any two examples.
5. With the help of diagrammatic representation only, show the steps of recombinant DNA
technology.
(DELHI 2008)
6. Answer the following question
7. Name the source of Taq polymerase. Explain the advantage of its use in biotechnology
8. Expand the name of the enzyme ADA. Why is this enzyme essential in the human body?
Suggest a gene therapy for its deficiency.
(A.I.CBSE 2009)
9. Answer the following questions:
10. Why are engineered vectors preferred by biotechnologists for transferring the desired
genes into another organism?
11. Explain how ‘ori’, “selectable marker” do and “cloning sites” facilitate cloning into the
vectors.
(FOREIGN 2009)
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CHAPTER 12
BIOTECHNOLOGY AND ITS APPLICATIONS
The critical areas of biotechnology are:
 Providing the best catalyst in the form of improved organism usually a microbe or pure
enzyme.
 Creating optimal condition through engineering for a catalyst to act.
 Downstream processing technologies to purify the protein/organic compound.
BIOTECHNOLOGICAL APPLICATIONS IN AGRICULTURE:
 Plants, bacteria, fungi and animals whose genes have been altered by manipulation are
called Genetically Modified Organisms (GMO).
 Advantages of Genetic Modification in plants.
 Made crops more tolerant to abiotic stresses (cold, drought, salt, heat)
 Reduce reliance on chemical pesticides (pest resistant crop)
 Helped to reduce post harvest losses.
 Increased efficiency of mineral usage by plants.
 Enhanced nutritional values of food e.g. vitamin A enriched rice.
Bt Cotton:
 Some strains of Bacillus thuringiensis produce proteins that kill certain insects such as
lepidopterans (tobacco budworm, armyworm), coleopterans (beetles) and dipterans (flies,
mosquitoes).
tobacco budworm
armyworm
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 B.thuringiensis forms protein crystals
during a particular phase of their
growth. These crystals contain a toxic
insecticidal protein.
 These proteins are present in inactive
protoxin form, but become active toxin
in the alkaline pH of insect gut.
 The activated toxin binds to the
surface of midgut epithelial cells and
create pores that cause cell swelling
and lysis and eventually cause death of
insect
beetles
 Specific Bt toxin genes were isolated
form B. thuringiensis and genetically transferred to several plants such as cotton.
 Crystal proteins are produced by a gene called cry in B. thuringiensis.
 The protein coded by genes cryIAc and cryIIAb control the cotton bollworms.
 The protein coded by gene cryIAb controls corn borer.
Tobacco bollworms
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Bollworms
bollworms
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Corn borer.
Pest resistant plants:
 Several nematodes parasitize a wide variety of plants and animals including human
beings.
 A nematode Meloidegyne incognitia infects the root of tobacco plants and causes a great
reduction in yield.
 Strategy based on RNA interference (RNAi) prevents this infestation.
 Process by which double-stranded RNA (dsRNA) directs sequence-specific degradation
of mRNA
Steps of RNA interference:
 Double stranded RNA is produced endogenously or exogenously.
 Using Agrobacterium vectors nematode specific genes were introduced into the host
plant (tobacco plant).
 Introduction of DNA produces both sense and antisense RNA in the host.
 These two RNA’s being complementary to each other formed a double stranded
(dsRNA) that initiated RNAi.
 The dsRNA injected into the host plant from outside called exogenous dsRNA.
 The dsRNAs are cleaved into 21-23 nt segments (“small interfering RNAs”, or siRNAs)
by an enzyme called Dicer.
 siRNAs are incorporated into RNA-induced silencing complex (RISC)
 Guided by base complementarity of the siRNA, the RISC targets mRNA for degradation.
 The consequence was that the parasite could not survive in a transgenic host.
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BIOTECHNOLOGICAL APPLICATIONS IN MEDICINE:
 Biotechnology enables mass production of safe and more effective therapeutic drugs.
 Recombinant therapeutics does not induce unwanted immunological responses as is
common in case of similar products isolated from non-human sources.
 At present around 30 recombinant therapeutics, approved for human-use.
Genetically Engineered Insulin:




Taking insulin at regular interval of time is required for adult-onset diabetes.
Previously the source of insulin was the slaughtered cattle and pigs.
This insulin caused allergy in some patients.
Each insulin made of two short polypeptide chains; chain A and chain B that are
linked together by disulphide linkage.
 Insulin synthesized in pancreas as prohormone
which is a single polypeptide with an
extra
stretch called C-peptide.
 C-peptide is removed during matured
insulin.
 In 1983 Eli Lilly an American company
prepared
two
DNA
sequences
corresponding to A and B, chains of human
insulin and
introduced them in plasmids of E.coli to produce insulin chains.
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 Chain A and chain B produced separately, extracted and combined by creating
disulfide bonds to form mature human insulin.
Gene therapy:
 Gene therapy is an attempt to cure hereditary or genetic diseases.
 Genes are inserted into a person’s cells and tissue to treat the disease.
 The first clinical gene therapy was given in 1990 to a 4-yr old girl with adenosine
deaminase (ADA) deficiency.
 This enzyme is required for breakdown of deoxyadenosine into uric acids.
 In the absence of ADA toxic deoxyadenosine is accumulated and destroy the infection
fighting immune cells called T-cells and B-cells.
 This disorder is caused due to the deletion of the gene for adenosine deaminase in
chromosome 20.
Treatment:
 Treated by bone marrow transplantation.
 Enzyme replacement therapy, involving repeated injections of the ADA enzyme
 Lymphocytes from the blood of the patient are grown in a culture. A functional ADA
cDNA is then introduced into these lymphocytes and returned into the body.
 The patient required periodic infusion of genetically engineered lymphocytes because
these cells are not immortal.
 Functional ADA cDNA introduced into cells at early embryonic stages, could be the
permanent cure.
Molecular diagnosis:
 Early detection of disease is not possible by conventional methods (serum and urine analysis)
Molecular diagnosis techniques:
 Recombinant DNA technology.
 Polymerase chain reaction (PCR)
 Enzyme linked Immuno-sorbent Assay (ELISA)
 Very low concentration of a bacteria or virus can be amplified and detected by PCR.
 It used to detect genetic disorders.
 PCR is use full to mutation in genes in suspected cancerous patient:
 A single stranded DNA or RNA tagged with radioactive molecule (probe) is
allowed to hybridize to its complementary DNA in a clone of cells followed by
detection using autoradiography.
 The clone having mutated gene unable make complementary bonding of probe,
hence not appears in photographic film.
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TRANSGENIC ANIMALS:
 Animals that have an alien DNA which able to express in it is called transgenic animals.
Reasons for creation of transgenic animals:
 Normal physiology and development:
 Transgenic animals are specifically designed to allow study of:
 How the genes are regulated.
 How the gene affects normal functioning of body
 How it affects growth and development.
e.g. insulin like growth factor.
 The animals made transgenic to know the biological effect and result.
 Study of disease:
 Transgenic animals are designed to understand how genes contribute to the
development of disease like cancers, cystic fibrosis, rheumatoid arthritis and
Alzheimer’s.
 Biological products:
 Transgenic animals are used to produce biological product of human interest:
 α-1-antitrypsin used to treat emphysema.
 Proteins for treatment for PKU and cystic fibrosis.
 Transgenic cow Rosie, produce human protein enriched milk (2.4
gm/lit. human α-lactalbumin)
 Vaccine safety:
 Transgenic mice are being developed and use in testing the safety of vaccines
before they are used for humans.
 Polio vaccine is tested in mice.
 Chemical safety testing:
 This is also known as toxicity/safety testing.
 Transgenic animals are made to known the effect of toxic chemicals.
ETHICAL ISSUES:
 GEAC (Genetic Engineering Approval Committee) set up by Indian Govt, which will make
decisions regarding validity of GM research and safety of introducing GM-organisms for
public services.
 A patent is the right granted by a government to an inventor to prevent others from
commercial use of his invention.
 Patents granted for biological entities and for products derived from them; these patents are
called biopatents.
 27 documented varieties of Basmati are grown in India.
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QUESTION FOR THE CHAPTER
F.M. 35
SECTION- A
1.
Name the gene that codes for Bt toxin. (1)
2.
Write the full form of the ELISA. (1)
3.
Name a human protein produced in the transgenic cow named Rosie.(1)
4.
What is the difference between ‘Cry’ & ‘cry’? (1)
5.
Thermostable DNA polymerase is needed in amplification? Why?
SECTION – B
6. Give the technical term for following
(a) Molecular scissors.
(b) Autonomous replicating circular DNA
(c) First isolated restriction endonuclease
7. A functional ADA cDNA is introduced into lymphocyte during Gene therapy. But the patient
needs periodic infusion? What is the permanent cure in such situation?
8. What is the role of Cry I Ac, Cry II Ab and Cry I Ab
9. Many proteins are secreted in their inactive form. This is also true of many toxic proteins
produced by micro organisms. Explain how the mechanism is useful for the organism
producing the toxin?
10. What do you mean by “Biopiracy” Give an example?
SECTION – C
11. What do you mean by RNA interference (RNAi)? Describe the mechanism by which this
strategy is used in controlling nematode parasite in tobacco plants.
12. What are Cry proteins? Name an organism that produces it. How has man exploited this
protein to his benefit?
13. Why is it that the line of treatment for a genetic disease is different from infectious diseases?
14. ELISA technique is based on the principles of antigen-antibody interaction. Can this
technique be used in the molecular diagnosis of a genetic disorder, such as phenyketonuria?
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15. Write the matching word:-A
B
(1)Hind II
Gel electrophoresis
(2)Separation of DNA fragments
At tetracycline resistance gene
in vector pBR 322
(3) BamH I
first restriction endonuclease
SECTION - D
16. Complete the steps for separation and isolation of DNA fragments.
(a) Cutting of DNA by --------------------------(b) During --------------- DNA fragments move to---------------------(c) --------fragments move -----------------where as large remains nearer.
(d) DNA fragments are stained with -----------------(e) Fragments are extruded from gel piece. This is known as -------------------.
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CHAPTER- 12
BIOTECHNOLOGY AND ITS APPLICATIONS
VERY SHORT ANSWER TYPE QUESTION (1 MARK)
2.
1.
Name the genes codes for protein that kills cotton bollworms.
2.
Which gene in the Bacillus thuringiensis codes for a protein that kills corn borer?
3.
Name the nematode that infects the roots of tobacco plant and causes a great reduction in
yield.
4.
In what ways the recombinant therapeutics are better than that isolated from non-human
sources?
5.
What you call to that extra stretch of polypeptide present along with insulin.
6.
What is the principle of ELISA test?
7.
Which human protein produced by rDNA technology, used to treat emphysema?
8.
Why the milk produced by the transgenic cow Rosie then natural cow milk?
9.
Which Indian Govt. organization has been set up to make decisions regarding the validity
of GM research and the safety of introducing GM-organisms for public services?
10.
Name the genetically engineered human Insulin?
11.
Write the Scientific name of nematode that attacks the root of tobacco plant?
12.
Define a patent?
13.
Expand GEAC.
14.
Name the first transgenic cow?
15.
Which vaccine was being tested on mice?
16.
Name the bacterium which is used to produce insect-resistant plants by genetic
engineering.
17.
Name any disease against which vaccine is developed by Recombinant DNA technology.
18.
Name the technique which is used to detect HIV in Suspected AIDS patient?
19.
Name any two diseases for which transgenic mice are used as model organisms.
20.
Name any one disease for which gene therapy has been proved effective?
21.
Name the molecular diagnostic techniques that should be referred to any patient for early
diagnosis.
22.
Give the term for rDNA, PCR and ELISA have common value
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23.
Give the term for replacing a defective mutant allele with a functional allele.
24.
Give the term for increasing the content of gene
25.
What is the principle of ELISA?
26.
What is common in the recognition sequence of all the organisms and strains, which are
recognized by restriction enzymes
27.
Can you recall meiosis and indicate at what stage a recombinant DNA in made?
28.
What is golden rice?
29.
Does your blood have proteases and nuclease? If so what is its function?
30.
Which enzyme is used to remove phosphate group from the 5’ end of a DNA molecule
31.
Bioreactors are important aspect of Bio technology .How?
32.
Name the Genetically engineered human insulin. How many amino acids are present in
it?
33.
Out of 51 amino acids in insulin. How many amino acids present in chain A and B.
34.
India is the world’s richest country in the Bio diversity .how is it affected
35.
What is the difference between these two plasmids?
A
36.
B
Eukaryotic organisms do not have restriction endonuclease. What is its role in
prokaryotes?
SHORT ANSWER TYPE QUESTION (2 MARK)
1. How application of biotechnology in agriculture able to produce pest resistance plant?
2. Describe the mechanism; how the insecticidal protein produces by the bacterium unable
to kill the bacterium instead it kills a group of insects?
3. Which categories of insect does the Bt toxin kill?
4. Expand the term ADA. What it its role?
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5. This figure shows the inhibition of mRNA transcription using antisense technology. The
red molecule in this example is called _______, and it inhibits translation by _______.
6. What is Golden rice? What is its advantage?
7. What are the three critical research areas in the field of Biotechnology?
8. What are the advantages of molecular diagnostics over conventional methods?
9. What are genetically modified organisms? Name two factors on which their behaviour
depends?
10. What are transgenic Bacteria? Illustrate using any one example?
11. Give any two examples of products, how transgenic animals can be used to
produce biological compounds?
12. How is autoradiography used to detect a mutated gene?
13. Why Bacterial toxin did does not kill the bacteria but only the insects?
14. Mention any four applications of Biotechnology in the field of Agriculture?
15. Why is recombinant Insulin produced by genetic engineering need to be processed?
16. In view of the current food crisis, it is said, that we need another green revolution.
Highlight the major limitations of the earlier green revolution.
17. Expand GMO. How is it different from a hybrid?
18. Differentiate between diagnostics and therapeutics. Give one example and for each
category.
19. Give the full form of ELISA. Which disease can be detected using it? Discuss the
principle underlying the test.
20. Can a disease be detected before its symptoms appear? Explain the principle involved.
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21. Write a short note on Biopiracy highlighting the exploitation of developing countries by
the developed countries.
22. While creating genetically modified organisms, genetic barriers are not respected. How
can this be dangerous in the long run?
23. Why has the Indian Parliament cleared the second amendment of the country’s patents
bill?
24. Give any two reasons why the patent on Basmati should not have gone to an American
Company.
25. How was Insulin obtained before the advent of rDNA technology? What were the
problems encountered?
26. Name the recognition site and the antibiotic resistant gene found in pBR 322.
Recognition site
Antibiotic resistance gene
Pvu 1, Pst 1
________(1)___________
tetR
_(2)___ , Sal 1
27. With respect to understanding diseases, discuss the importance of transgenic animal
models.
28. Name the first transgenic cow. Which gene was introduced in this cow?
29. PCR is a useful tool for early diagnosis of an infectious disease. Elaborate.
30. What is GEAC and what are its objectives?
31. For which variety of Indian rice, the patent was filed by a USA Company?
32. Discuss the advantages of GMO.
33. What is the basis upon which the discipline of Biotechnology was founded by Boyer and
Cohen?
34. The source of EcoR I restriction enzyme is E-coli RY 13.
35. Give the sticky end of this bacteria
36. Name the source of EcoR II
37. One of the easily manipulated plasmid used as a vector is pBR 322. What is the letter p,
B, R and 322 signify?
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(-)
(+)
38. The electrophoresis apparatus is given above
(a) In which direction the DNA fragment resolve and why?
(b)Where do you find the smallest and the largest fragment of DNA in the agarose
gel?
39. Complete the following table:-Process
Aim
(1)
Preserves genetic information
Sexual reproduction
(2)
(3)
Leads
to
multiplication
including
and
Of desired as well as undesired
genes
Genetic engineering
(4)
40. Three steps to produce genetically modified organisms are
Identification of DNA with _____________ (1) ______________
Introduction of identified DNA to _______ (2) _____________
Maintenance of DNA in host and transfer to _______(3)_________
41. Name the following:(i) 5’- GAATTC- 3’
3’- CTTAAG- 5’ ------------------(ii)
(iii)
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(iv)
42. Name the enzyme involved in the following process:-(d) Inspecting the DNA length for pallindromic nucleotide sequence
(e) Joining of DNA fragments
(f) Breaking of cell to release DNA and other macromolecules
(g) Repeated DNA fragments.
43. Karl Ereky and Paul Berg are related to Biotechnology. Find their contribution.
44. Name the following
(a) Drug that was produced from slaughtered animals but now produced by using
Biotechnology.
(b) Technique used to detect the presence of virus in human.
45. Differentiate ‘Cry’ and ‘cry’
46. Give the term for
The DNA formed by joining together DNA from two different organisms and
The DNA obtained from an RNA template using the enzyme reverse transcriptase.
47. What are the functions of enzymes isolated by Stewart Linn and Werner Arber?
48. What is the difference between stirred tank bioreactor and sparged stirred tank
bioreactor? What is its advantage?
49. Give the options to increase food production?
50. Why do we still search for other alternatives to increase food production?
SHORT ANSWER TYPE QUESTION (3 MARKS)
1. What are the three critical research areas of biotechnology?
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2. What are the three options in the field of agriculture that can be thought for increasing
food production?
3. Describe the mechanism and the principle by which a transgenic tobacco plant get
resistance to the specific nematode.
4. You want to produce human insulin by rDNA technology. Describe the mechanism you
would follow to produce that hormone.
5. Write the full form of PCR. Write its three important applications in relation to molecular
diagnosis.
6. Describe briefly how a mutated gene is being identified by polymerase chain reaction or
PCR technique?
7. What do you mean by Biopiracy? Explain it with suitable example.
8. Describe with example, why transgenic animals are produced?
9. Describe how nematode – resistant transgenic plants have been obtained?
10. Write an account on the production of human insulin in transgenic organisms.
11. Compare & contrast the advantages & disadvantage of production of genetically
modified organisms?
12. What is RNA Silencing? How is this strategy used to create pest –resistant plants?
13. What are the steps involved in synthesis of genetically engineered insulin.
14. Gene expression can be controlled with the help of RNA. Explain the method with an
example.
15. Ignoring our traditional knowledge can we prove costly in the area of biological
patenting? Justify.
16. Highlight any four areas where genetic modification of plants has been useful.
17. What is a recombinant DNA vaccine? Give two examples.
18. Discuss briefly how a probe is used in molecular diagnostics.
19. Who was the first patient who was given gene therapy? Why was the given treatment
recurrent in nature?
20. Taking examples under each category, discuss upstream and downstream processing.
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21. Explain the process of curd formation from milk?
Milk is incubated with curd
↓
LAB grows in milk
↓
{1} Production
↓
Coagulation & digestion of milk protein
↓
Improved nutritional quality by {2}
(a) Complete the flow chart
(b) Expand the word LAB
(c) What is the role of LAB in human body?
22. Define Antigen and Antibody. Name any two diagnostic kits based upon them.
23. How is a mature, functional insulin hormone different from its prohormone form?
24. Transgenic animals are the animals in which a foreign gene is expressed. Such animals
can be used to study the fundamental biological process, phenomenon as well as for
producing products useful for mankind. Give one example for each type.
25. Gene therapy is an attempt to correct a genetic defect by providing a normal gene into the
individual. By this the normal function can be restored. An alternate method would be to
provide the gene product (protein/enzyme) known as enzyme replacement therapy, which
would also restore the function. Which in your opinion is a better option? Give reason for
your answer.
26. When a foreign DNA is introduced into an organism, how is it maintained in the host and
how is it transferred to the progeny of the organism?
27. Bt cotton is resistant to pest, such as lepidopteron, dipterans and coleopterans. Is Bt
cotton also resistant to other pests as well?
28.
a_DNA
b
DNA
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Study the linking DNA fragments shown above.
(a) Name ‘a’ DNA and ‘b’ DNA.
(b) Name the restriction enzyme that recognizes this palindrome.
(c) Name the enzyme that can link these two DNA fragments.
29. Complete the basic steps to create GMO
(a) ---------------------------with desired gene
(b) --------------------------- into host
(c) -------------------------into progeny
30. Which of the following is not a tool for constructing rDNA?
(a) Heat shock
(b) Microinjection
(c) Biolistics
(d) Disarmed pathogens
(e) Insertional inactivation
LONG ANSWER TYPE QUESTIONS (5 MARKS)
1. Define genetically modified organism. What are different ways that GM plants have been
useful?
2. Explain gene therapy with suitable example.
3. Define transgenic animal. Why these animals are being produced?
4. What is Gene therapy – Illustrate using example of Adenosine deaminase
deficiency?
5. A patient is suffering from ADA deficiency. Can he be cured? How?
6. Define transgenic animals. Explain in detail any four areas where they can be utilized.
7. Explain with the help of one example how genetically modified plants can:
(a) Reduce usage of chemical pesticides
(b) Enhance nutritional value of food crops
8. You have identified a useful gene in bacteria. Make a flow chart of the steps that you
would follow to transfer this gene to a plant.
9. Following are 3 lines of treatment of ADA deficiency disease
(a) Bone marrow transplantation
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(b) Enzyme replacement theory
(c) Gene therapy
Give advantages and drawbacks of each.
10. Highlight five areas where biotechnology has influenced our lives.
11. What are the various advantages of using genetically modified plants to increase the
overall yield of the crop?
12. List the disadvantages of insulin obtained from the pancreas of slaughtered cows
and pigs:
13. List the advantages of recombinant insulin.
14. What is meant by the term bio-pesticide? Name and explain the mode of action of a
popular bio-pesticide.
15. Name the five key tools for accomplishing the tasks of recombinant DNA technology.
Also mention the functions of each tool.
16. Find out how to make orally active protein pharmaceutical. What is the major problem to
be encountered?
17. How can the desired products formed after genetic engineering are produced on a
commercial scale?
18. Answer the following questions:
(a) Complete the labeling in the following PCR.
(b) Expand the word PCR.
(c) Give the origin of ‘Taq’
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(d) Why is heating done in the procedure?
19. Complete the following
(a) The pathogens which are transformed to make them non virulent are called
________pathogens.
(b) To isolate DNA from fungus cells, the later are treated with _________.
(c) The culture system where in the used medium is drained out from one side, while
fresh medium is added from the other is called _________.
20. Study the given flow chart and answer the questions.
(a) Name the defense mechanism used
(b) In which plant has it been done?
(c) Name the nematode infested.
21. Suggest a method to remove oil from seeds based on rDNA technology
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QUESTIONS FROM PREVIOUS YEARS BOARD PAPERS
CHAPTER-12.
BIOTECHNOLOGY AND ITS APPLICATIONS
VERY SHORT ANSWER TYPE QUESTION (1 MARK)
1. Why is the gene encoding for ‘Cry’ protein inserted into a crop plant?
(A.I.CBSE
2005)
2. What was the specialty of the milk produced by the transgenic cow Rosie? (CBSE 2008)
3. A multinational company outside India tried to sell new varieties of turmeric without
proper patent rights. What is such an act referred to?
(A.I.CBSE 2008)
4. What was the specialty of the milk produced by transgenic cow Rosie?
(DELHI-08)
5. A multinational company outside India tried to sell new varieties of turmeric without
proper patent rights. What is such an act referred to?
(DELHI 2008)
6. What is the significance of the process of RNA interference (RNAi) in eukaryotic
organisms?
(FOREIGN 2008)
7. What does the organization GEAC check with reference to genetic engineering?
(FOREIGN 2008)
8. How does silencing of specific mRNA in RNA interference prevent parasitic infestation?
(A.I.CBSE 2008 C)
9. What is the role of the organization GEAC?
(A.I.CBSE 2008 C)
10. Name the Indian variety of rice patented by an American company.
(DELHI2008)
11. How are Tobacco plants benefited when nematode specific genes are introduced into
them using certain vectors? Name the vectors used.
(A.I.CBSE 2008 C)
12. How is a transgenic tobacco plant protected against Meloidegyne incognitia? Explain the
procedure.
(A.I.CBSE 2009)
13. How Eli Lilly synthesize the human insulin? Mention one difference between this insulin
and the one produced by the human pancreas.
(A.I.CBSE 2010)
14. Name the molecular diagnostic technique to detect the presence of a pathogen in its early
stage of infection.
(DELHI 2010)
15. Name any two techniques that serve the purpose of early diagnosis of some bacterial/viral
human diseases.
(FOREIGN 2011)
16. Mention the source organism of the gene cryIAc and its target pest.
(FOREIGN 2011)
17. State the role of transposons in silencing of mRNA in eukaryotic cells. (A.I.CBSE 2013)
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SHORT ANSWER TYPE QUESTION (2 MARKS)
1. Describe the responsibility of GEAC, set up the Indian Government.
2. Highlight any four advantages of genetically modified organisms.
(DELHI 2009)
(FOREIGN 2009)
3. Nematode specific genes are introduced into the tobacco plants using Agrobacterium
vectors to develop resistance in tobacco plants against nematodes. Explain the events that
occur in tobacco plant to develop resistance.
(DELHI 2009)
4. List any four advantages of genetically modified crop plants over their wild/domesticated
relatives.
(CBSE-SP)
5. State the principle underlying ‘gel electrophoresis’ and mention two applications of this
(CBSE – SP)
technique in biotechnology.
6. You have developed a GM organism. Which government organization will you approach
to obtain clearance for its mass production? Why is such a body necessary? Give two
(CBSE – SP)
reasons.
7. A multinational company (XYZ) marked a medicine extracted from medicinal herbs
grown in the sprawling fields in a foreign country. This herb is found only in our country
and no compensation was paid or permission taken from relevant authority.
(a) What is the term used to refer to such an act committed by the multinational
company?
(b) Justify the meaning of the term.
(CBSE – SP)
(c) What has our government done to prevent such deeds?
8. How is Bt cotton made to attain resistance against boll worm?
(A.I.CBSE 2010 C)
9. Why an introduction of genetically engineered lymphocytes into an ADA deficiency
patient not a permanent cure? Suggest a possible permanent cure.
(DELHI 2010)
10. Why do the toxic insecticidal proteins secreted by Bacillus thuringiensis kill the insect
and not the bacteria itself?
(FOREIGN 2010)
11. Name the first transgenic cow developed and explain the improvement in the quality of
the product produced by it.
(FOREIGN 2010)
12. Explain the process of RNA interference.
(DELHI 2011)
13. Explain how a hereditary disease can be corrected. Give an example of first successful
attempt made towards correction of such disease.
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14. How ‘Rosie’ considered different from a normal cow? Explain.
15. Biopiracy should be prevented. State why and how?
(A.I.CBSE 2011)
(A.I.CBSE 2011)
16. Answer the following questions:
(a) Mention the cause and the body system affected by ADA deficiency in humans.
(b) Name the vector used for transferring ADA-DNA into recipient cells in humans.
Name the recipient cells.
A.I. CBSE 2012)
17. Why is proinsulin so called? How is insulin different from it?
(A.I.CBSE 2013)
SHORT ANSWER TYPE QUESTION (3 MARKS)
1. Answer the following questions:
(a) Give the scientific name of the soil bacterium, which produces crystal (Cry)
proteins.
(b) How are these proteins useful in agriculture?
(c) What do the differently written terms ‘Cry’ and cry represent respectively
(A.I.CBSE 2004)
2. Explain the principle and function of ELISA.
(A.I.CBSE 2005)
3. What is transgenic crop? State the advantage of the technique involved in the production
of transgenic crop over breeding activities.
(DELHI 2005)
4. Write the full form of ELISA. Give an example of clinical application of ELISA test.
(A.I.CBSE 2006)
5. State the principle on which ELISA technique is based. How does it help in early
detection of a disease?
(A.I.CBSE 2008 C)
6. What are bioreactors? List five growth conditions that a bioreactor provides for obtaining
the desired product.
A.I.CBSE 2008 C)
7. Plasmid is a boon to biotechnology. Justify this statement quoting the production of
human insulin as an example.
A.I.CBSE 2009)
8. Name the source and the types of cry genes isolated from it for incorporation into crops
by biotechnologists. Explain how these genes have brought beneficial changes in the
genetically modified crops.
(A.I.CBSE 2009)
9. What is the cause of adenosine deaminase deficiency in a person? Why it is that even
after infusion of genetically engineered lymphocytes into the patient suffering from
deaminase deficiency, the cure is not permanent?
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10. In case of Bt cotton, how does the toxic insecticide protein produced by the bacterium kill
the insect pest but not the cell of Bacillus thuringiensis where the toxic protein is
generated?
(CBSE- SP)
18. List any four advantages of genetically modified crop plants over their wild/domesticated
(CBSE – SP)
relatives.
19. In case of Bt cotton, how does the toxic insecticide protein produced by the bacterium kill
the insect pest but not the cell of Bacillus thuringiensis where the toxic protein is
(CBSE – SP)
generated?
20. Expand GEAC. Why was GEAC established? Mention the responsibilities assigned to
this organization.
(A.I.CBSE 2010 C)
21. Answer the following questions:
(a) Explain the effect of deletion of the gene for ADA in an individual.
(b) How does the gene therapy help in this case?
(A.I.CBSE 2010 C)
22. Answer the following questions:
(a) How biotechnology helped in producing Meloidegyne incognitia resistant tobacco
plant?
(b) Why does this nematode die on eating such a GM plant?
(DELHI 2010 C)
11. Two of the steps involved in producing nematode resistant tobacco plants based on the
process of RNAi are mentioned below. Write the missing steps in its proper sequence.
(CBSE – SP)
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23. How does RNA interference help in developing resistance in tobacco plant against
nematode infection?
(DELHI 2010)
24. Answer the following questions:
(a) Tobacco plants are damaged severely when infested with Meloidegyne incognitia.
Name and explain the strategy that is adopted to stop this infestation.
(b) Name the vector used for introducing the nematode specific gene in tobacco plant.
(A.I.CBSE 2012)
25. Name the pest that destroys the cotton bolls. Explain the role of Bacillus thuringiensis in
protecting the cotton crop against the pest to increase the yield.
(A.I.CBSE 2013)
LONG ANSWER TYPE QUESTIONS (5 MARKS)
1. Explain the steps involved in the production of genetically engineered insulin.
(A.I.CBSE 2008)
2. What is gene therapy? Illustrate using the example of adenosine deaminase (ADA)
deficiency.
(DELHI 2008)
3. Answer the following questions:
(a) What is plasmid?
(b) What is meant by ADA deficiency? How is gene therapy a solution to this
problem? Why is it not a permanent cure?
(FOREIGN 2008, DELHI 2008)
4. Explain the steps involved in the production of genetically engineered insulin.
(DELHI 2008)
5. Explain the steps involved in the production of genetically engineered insulin. Why is
insulin thus produced preferred to the one produced from non-human sources?
(FOREIGN 2008)
6. What are transgenic animals? Explain any four ways in which such animals can be
beneficial to humans.
(FOREIGN 2008)
7. Answer the following questions:
(a) Why Bacillus thuringiensis is considered suitable for developing GM plants?
(b) Explain how it has been used to develop GM crops?
8. Answer the following questions:
(FOREIGN 2008)
(A.I.CBSE 2008)
(a) Name the nematode that infests and damages tobacco roots.
9. How are transgenic tobacco plants produced to solve this problem?
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10. One of the main objectives of biotechnology is to minimize the use of insecticide on
cultivated crop. Explain with suitable example how insect resistant crop has been
developed using techniques of biotechnology.
(DELHI 2009)
11. How is transgenic tobacco plant protected against Meloidegyne incognitia(CBSE 2009)
12. Answer the following questions:
(a) Name the source of Taq Polymerase. Explain the advantage of its use in
biotechnology.
(b) Expand the name of enzyme ADA. Why is this enzyme essential in human body?
Suggest a gene therapy for its deficiency.
(FOREIGN 2009)
13. Answer the following questions:
(a) How is a transgenic tobacco plant protected against Meloidegyne incognitia?
(b) Explain the procedure for making such plant.
(FOREIGN 2009)
14. Answer the following questions:
(a) How mature insulin is different from proinsulin secreted from the pancreas in
human.
(b) Explain how human functional insulin produced using rDNA technology.
(c) Why is the functional insulin thus produced considered better than the one used
earlier by diabetic patients?
(DELHI 2009)
15. With an example, explain how biotechnology has been applied in each of the following:
(a) In curing Diabetes mellitus
(b) In raising pest resistant plants
(c) In producing more nutritionally balanced milk.
(CBSE – SP)
Do you think it is ethical to manipulate organisms for human benefits? Justify your
answer
16. Name any two cloning vectors. Describe the features required to facilitate cloning into a
(CBSE – SP)
vector.
17. Answer the following questions:
(a) Name the source from which insulin was extracted earlier. Why is this insulin no
more in use by diabetic people?
(b) Explain process of synthesis of insulin by Eli Lilly Company. Name the technique
used by the company.
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(c) How is the insulin produced by human body different from the insulin produced
by the above mentioned company?
(A.I.CBSE 2011)
18. Name the process involved in the production of nematode-resistant tobacco plants, using
genetic engineering. Explain the strategy adopted to develop such plants.
(FOREIGN 2011)
19. Describe the various stages involved in gene transfer for the commercial production of
human insulin by Ely Lilly.
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(FOREIGN 2011)
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