(a) Name the particular technique in Biotechnology, whose steps are shown in the figure.
(b) Name the steps 1 to 4 marked in the figure.
(c) Give an example where a human gene product is. obtained from transgenic bacteria.

(a) Name and write the significance of enzyme X.
(b) Name and write the role of enzyme Y.
(c) Name the processes A and B.

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.

The following diagram illustrates the linking of DNA fragements. Answer the questions that follow the illustration.

(a) Name 'a' and 'b'.
(b) Complete the palindrome, which is recognised by EcoRI.
(c) Name the enzyme that can link the two DNA fragments.

(a) What does the diagram given above, depict?
(b) What is meant by 'largest' and 'smallest' in the diagram'?
(c) Name the compound used to visualise them.
(d) Define elution.

A picture of gel electrophoresis showing the separation of DNA fragments is shown above. Answer the following questions.
(a) Identify the positive and negative terminals.
(b) What is the matrix used and mention its source?
(c) Identify the undigested DNA.

The E.coli cloning vector pBR322 is shown above.
(a) Identify and name two selectable markers.
(b) Identify and name the restriction enzymes that can be used to ligate an alien DNA fragment at the tetracycline gene.
(c) Identify EcoRI.
(d) Name the gene that controls the copy number of the vector.

A schematic representation of the steps in Polymerase Chain Reaction (PCR) is shown below. Answer the questions that follow:

(a) Name the steps A and D in the PCR.
(b) Identify B. What are they chemically?
(c) What is C? Name its source organism.

(a) Name the type of bioreactor shown above.
(b) Why does it have a curved base?
(c) What is the significance of the stirrer?

When a gene product is required in large quantities, the transformants with N2 the plasmid inside the cell are cultured in a large scale in an industrial fermenter, which then synthesise the desired protein. This product is extracted from the fermenter for commercial use.
(a) Why is the used medium drained out from one side while the fresh medium is added from the other. Explain.
(b) List any four optimum conditions for achieving the desired product in a bioreactor.

Read the following and answer any four questions from (i) to (v) given below:
Gene manipulation is a fast emerging science. It started with development of recombinant DNA molecule. It is named variously as DNA manipulation biotechnology, recombinant DNA technology and genetic engineering. This technology, that mostly involves cutting and pasting of desired DNA fragments, is based on two important discoveries in bacteria, i.e., presence of plasmid in bacteria and restriction endonucleases. Paul Berg was able to introduce a gene of SV-40 into a bacterium. The science of recombinant DNA technology took birth when Cohen and Boyer (1973) were able to introduce a piece of gene containing foreign DNA into plasmid of E.coli.
(i) Biotechnology is also known as

(ii) A bacterial plasmid is a/an

(iii) Father of genetic engineering is

(iv) Which of the following is used by Paul Berg to introduce a gene of SV-40 in a bacterium?

(v) Read the given statements and select the correct option.
Assertion : Biotechnology started with the development of recombinant DNA molecule.
Reason : Biotechnology mostly involves cutting and pasting of desired DNA fragments.

Read the following and answer any four questions from (i) to (v) given below:
Restriction endonuclease was isolated for the first time by W Arber in 1962 in bacteria. Restriction endonucleases cut the DNA duplex at specific points therefore they are also called as molecular scissors or biological scissors. Three types of restriction endonucleases are Type I, Type II and Type III but only Type II restriction endonucleases are used in recombinant DNA technology. Restriction endonuclease EcoR I recognises the base sequence GAATTC in DNA duplex and cut strands between G and A.
(i) Only type II restriction enzymes are used in gene manipulation because

(ii) Which of the following ions are used by restriction endonucleases for restriction?

(iii) Restriction endonuclease was isolated for the first time in a

(iv) Restriction endonucleases are also called as molecular or biological scissors because

(v) Select the option that correctly states the working action of restriction endonuclease EcoR 1 on DNA sequence GAATTC

Read the following and answer any four questions from  (i) to (v) given below:
Tools used in the formation of recombinant DNA are of three types. These are enzymes, cloning vectors and competent host. Lysing enzymes are used to extract DNA for experimental purpose from the cells. Cleaving enzymes break the DNA molecules. They are of three types : exonucleases, endonucleases and restriction endonucleases. A competent host is required for transformation with recombinant DNA and cloning vectors help to propagate DNA.
(i) Which of the following is an example of natural lysing activity in a human body?

(ii) The enzyme which has polymerizing activity in 5'→3' direction but exonuclease activity in 3'→ 5' direction only is

(iii) Cloning vectors are the DNA molecules that

(iv) Transfer of DNA into a eucaryotic cell is called

(v) Assertion: Type I restriction enzymes are not used in rDNA technology.
Reason: Type I restriction endonucleases consist of two different subunits and require ATP for restriction activity.

Read the following and answer any four questions from (i) to (v) given below:
The foundations of recombinant DNA (rDNA) were laid by the discovery of restriction enzymes. These enzymes are present in many bacterias where they function as a part of their defense mechanism called the Restriction Modification system (RM system). Molecular basis of this system was explained first by Werner Arber in 1962. The Restriction t-'l0dification system consists of two components:
1. A restriction enzyme (called restriction endonuclease) identifies the introduced foreign DNA and cuts it into pieces.
2.The second component is a modification enzyme (methylase) that adds a methyl group to DNA at specific site to protect it from the restriction enzyme cleavage.
(i) Restriction endonucleases are enzymes present in (i) where they function as a part of (ii) mechanism.

(ii) Which of the following statements regarding modification enzyme is correct?

(iii) Which of the following is a type II restriction enzyme?

(iv) Which of the following is the first discovered restriction endonuclease?

(v) Components of Restriction Modification System include

Read the following and answer any four questions from (i) to(v) given below:
In recombinant DNA technology, the fragments of DNA generated after cutting the DNA by restriction enzymes are separated according to their size or length by gel electrophoresis. Gel electrophoresis is performed in a gel matrix so that molecules of similar electric charges can be separated on the basis of size. Most commonly used matrix in gel electrophoresis is agarose. The fragments are separated under the influence of electric field. The separated DNA fragments can be seen only after staining the DNA with compound known as ethidium bromide (EtBr) followed by exposure to UV radiation as bright orange band.
(i) Gel electrophoresis is used for the separation of

(ii) Most commonly used matrix is (i) which is a (ii) extracted from (iii).

(iii) A DNA molecule was treated with a restriction endonuclease and three fragments of size (i) 426 kb, (ii) 129 kb and (iii) 46 kb were obtained. Identify the order in which these bands will arrange themselves in the gel plate after gel electrophoresis is completed. (Assuming that negative part of electrode is towards the well)

(iv) Which of the following statements regarding gel electrophoresis is incorrect?

(v) The factor that will not affect the rate of DNA migration in gel electrophoresis is