(a) Refer Quick Review (Same value points to be awarded in an explanation) 
(b) Purpose : Used to ligate with a vector for further cloning. Detection of bacteria or virus by amplification of their DNNdetection of HIV in AIDS patient. Detection of mutation in genes in suspected cancer patients.

(a) DNA sequences of the vector as well as the source are cut by the same restriction enzyme like EcoRI, in a palindromic sequence. (The cut ends overhang to as sticky ends in the medium.)
(b) These cut ends fragments are to be extracted from the culture medium using gel electrophoresis. This has an agarose gel matrix. Fragments are fed in the wells. They are negatively charged. So, they move towards anode under an electric field through the gel. Smaller fragments move faster, thus separated.
(c) Fragments are now added to the medium containing the vector DNA. The sticky ends facilitates the action of the enzyme ligase and join the source DNA to the vector.

Chitinase It is an enzyme used to break the cell wall of fugi to release its cellular parts. Certain plants and fungus consist of a cell wall composed of chitin, which provides strength to the cell. Chitinase is used when there is a need to break this wall and allow entry of foreign DNA in plant cells.

(i) Single target site is present for particular restriction enzyme. If more than one site is present, then more cuts would fragment the plasmid.
(ii) 

(iii) (a) Now a days antibiotic resistance gene as markers are not used as they create more risk of plasmids to resistant gene to other bacteria.
It may spread the antibiotic resistance in many bacteria.
(b) Reporter genes are used now a days instead of antibiotic resistance genes. These genes have an ability to produce color in the presence of chromogenic substrate.

(i) Clones are identical copies of an organism produced by biotechnological methods.
(ii) In plants, clones are produced by clonal propagation using tissue culture technique.
(iii) Shilpi was curious to enhance her knowledge about biotechnological techniques.

(i) Biotechnology is the study of interchanged use of biochemistry, microbiology and engineering sciences in order to achieve technological application of the capabilities of microorganisms, cultured cells/tissue and parts thereof.
(ii) These are formed by integration of a segment of DNA of the bacterium Agrobacterium tufmefaciens into the host DNA.
(iii) His desire to know the latest developments in science.

Small volume cultures cannot yield appreciable quantities of products. To produce these products in large quantities the development of 'bioreactors' was required where large volumes (100-1000 litres) of culture can be processed. Thus bioreactors can be thought of as vessels in which raw materials are biologically converted into specific products, using microbial, plant, animal or human cells or individual enzymes.
Role. A bioreactor provides the optimal conditions for achieving the desired product by providing optimum growth conditions (temperature, pH, substrate, salts, vitamins, oxygen). One of the most commonly used bioreactor is of stirring type. A stirred tank reactor is usually cylindrical or with a curved base to facilitate the mixing of the reactor contents. The stirrer facilitates even mixing and oxygen availability throughout the bioreactor. Alternatively air can be bubbled 1lhroughthe reactor. If you look at the figure closely you will see that the bioreactor has an agitator system; an oxygen delivery system, a foam control system, a temperature control system, pH control system, sampling ports so that small volumes of the culture can be withdrawn periodically.

Small volume cultures cannot yield appreciable quantities of products. To produce these products in large quantities the development of 'bioreactors' was required where large volumes (100-1000 litres) of culture can be processed. Thus bioreactors can be thought of as vessels in which raw materials are biologically converted into specific products, using microbial, plant, animal or human cells or individual enzymes.
Role. A bioreactor provides the optimal conditions for achieving the desired product by providing optimum growth conditions (temperature, pH, substrate, salts, vitamins, oxygen). One of the most commonly used bioreactor is of stirring type. A stirred tank reactor is usually cylindrical or with a curved base to facilitate the mixing of the reactor contents. The stirrer facilitates even mixing and oxygen availability throughout the bioreactor. Alternatively air can be bubbled 1lhroughthe reactor. If you look at the figure closely you will see that the bioreactor has an agitator system; an oxygen delivery system, a foam control system, a temperature control system, pH control system, sampling ports so that small volumes of the culture can be withdrawn periodically.

(a) Role of Vectors
Ethidium bromide
The vectors have the ability to replicate within the bacterial cells independent of the control of chromosomal DNA.
If an alien piece of DNA is linked to the vector, it can be made to multiply its number equal to the copy number of the vector.
Vectors are also used in the selection of recombinants from non-recombinants.
e.g., plasmids and bacteriophages are the most commonly used vectors.