Explore topic-wise InterviewSolutions in .

i. The desired DNA segment is inserted into a cloning vector and the bacterial cell can be made to take it up after making them competent by treating them with specific concentration of divalent cations such as calcium.

ii. Microinjection

iii. Biolistics

iv. Disarmed pathogen vector

The source is the bacterium Thermus aquaticus. It is used because it is thermostable and do not denature at high temperatures.

European Federation of Biotechnology.

Biolistic gun is used to introduce alien DNA into the plant cell by bombarding them with high velocity microparticles (gold or tungsten coated with DNA).

a—gene for ampicillin resistance

d—gene for tetracycline resistance

In Hybridoma technology, mAbs are produced by fusing antigen-activated B lymphocytes that have been immortalised with myeloma cells using polyethylene glycol. This technique was developed by Ceasar Milstein and George Kohler (Nobel Prize winners). The hybrid cells retain the ability of B cells to secrete antibody and the ability of myeloma cells to grow indefinitely. The hybrid clones when grown in culture produce epitope-specific mAb.

Antibodies bind to specific domains of antigens known as epitopes. The antibodies present in serum are a heterologous population released by different populations of B-Iymphocytes and therefore are known as polyclonal antibodies. The polyclonal antibodies can bind to related epitopes and are therefore do not give accurate results in diagnostics. Monoclonal antibodies (mAbs), on the other hand bind specifically to an epitope on an antigen and therefore are useful in detecting specific antigens (diagnostics) or blocking their binding by other molecules. Monoclonal antibodies provide accurate results and are therefore used in diagnostics.

Hybridoma technology has revolutionized the area of diagnostics and antibody-based therapies. The availability of monoclonal antibodies has helped in early detection of many infectious diseases like hepatitis and AIDS. 

(a) Bacteria I are grown in a medium with chrornogenic substrate,colonies formed show blue colour-no recombinants, no blue colour presence of recombinants.

(b) Gene for the enzyme is inactivated by insertion.

For fulfilling the need of life human have been producing various food products by use of fermentation, selecting crop plants, developing livestock and obtaining their products. This is called traditional biotechnology.  Plant and animal tissue culture, genetic engineering, r-DNA technology, nanotechnology, production of monoclonal antibodies, etc. are the techniques used presently for human welfare and this is called modern biotechnology.

1. Transgenic animals are genetically modified animals that are used in a wide range of fields. 

2. In the field of medical research, transgenic animals like mice are used to identify the functions of specific factors through over- or under-expression of a modified gene (the inserted transgene). They are designed to study how genes contribute to the development of disease. These animals are used to investigate development of diseases like cancer, cystic fibrosis, rheumatoid arthritis, etc. 

3. In toxicology field, they are used for detection of toxicants. They are used as responsive test animals. Transgenic animals are used to evaluate a specific genetic change in molecular biology studies. 

4. In pharmaceutical industry, transgenic animals are used for targeted production of pharmaceutical proteins, drug production and product efficacy testing. 

5. They are also used in study of mammalian developmental genetics.

Transgenic farm animals like cattle, sheep, v poultry, pigs, etc. exhibit many desirable traits.

1. Improved quantity and quality of meat 

2. Improved quality and quantity of milk 

3. More egg production 

4. Better quality and quantity of wool 

5. Disease resistance 

6. Production of low-cost pharmaceuticals and biologicals

Correct answer is (d) both (a) and (b)

pBR 322 is Most commonly used plasmid in r-DNA technology.

Correct answer is (b) flu

Correct answer is (d) tobacco