Bioremediation:
It is defined as the use of microorganisms or plants to clean up environmental pollution.
Some examples of bioremediation technologies are :
(i) Phytoremediation - use of plants to bring about remediation of environmental pollutants.
(ii) Mycoremediation - use of fungi to bring about remediation of environmental pollutants.
(iii) Bioventing is the process that increases the oxygen or air flow to accelerate the degradation of environmental pollutants.
(iv) Bioleaching is the use of microorganisms in solution to recover metal pollutants from contaminated sites
(v) Bioaugmentation is the addition of selected microbes to speed up degradation process.
(vi) Composting is the process by which the solid waste is composted by the use of microbes into manure which acts as a nutrient for plant growth.
(vii) Rhizofiltration is the uptake of metals or degradation of organic compounds by rhizosphere microorganisms
(viii) Rhizostimulation is the stimulation of plant growth by the rhizosphere by providing better growth condition or reduction in toxic materials

Applications of Biotechnology
1. Biotechnology is one of the most important applied interdisciplinary sciences of the 21st century. It is the trusted area that enables us to find the beneficial way of life.
2. Biotechnology has wide applications in various sectors like agriculture, medicine, environment and commercial industries.
3. This science has an invaluable outcome like transgenic varieties of plants e.g. transgenic cotton (Bt-cotton), rice, tomato, tobacco, cauliflower, potato and banana.
4. The development of transgenics as pesticide resistant, stress resistant and disease resistant varieties of agricultural crops is the immense outcome of biotechnology.
5. The synthesis of human insulin and blood protein in E.coli and utilized for insulin deficiency disorder in human is a breakthrough in biotech industries in medicine.
6. The synthesis of vaccines, enzymes, antibiotics, dairy products and beverages are the products of biotech industries.
7. Biochip based biological computer is one of the successes of biotechnology.
8. Genetic engineering involves genetic manipulation, tissue culture involves aseptic cultivation of totipotent plant cell into plant clones under controlled atmospheric conditions.
9. Single cell protein from Spirulina is utilized in food industries.
10. Production of secondary metabolites, biofertilizers, biopesticides and enzymes.
11. Biomass energy, biofuel, bioremediation and phytoremediation for environmental biotechnology.

Modern biotechnology
(i) There are two main features of this technology, that differentiated it from the conventional technology are its
i) ability to change the genetic material for getting new products with specific requirements through recombinant DNA technology
ii) ownership of the newly developed technology and its social impact.
(ii) Modern biotechnology embraces all methods of genetic modification by recombinant DNA and cell fusion technology.
The major focus of biotechnology are
(i) Fermentation for production of acids, enzymes, alcohols, antibiotics, fine chemicals, vitamins and toxins
(ii) Biomass for bulk production of single cell protein , alcohol, and biofuel
(iii) Enzymes as biosensors, in processing industry
(iv) Biofuels for production of hydrogen, alcohol, methane
(v) Microbial inoculants as biofertilizer, and nitrogen fixers
(vi) Plant and animal cell culture for production of secondary metabolites, monoclonal antibodies
(vii) Recombinant DNA technology for production of fine chemicals, enzymes, vaccines, growth hormones, antibiotics, and interferon.
(viii) Process engineering - tools of biotechnology is used for effluent treatment , water recycling.

Biopharming also known as molecular pharming is the production and use of transgenic plants genetically engineered to produce pharmaceutical substances for use of human beings. This is also called "molecular farming or pharming". These plants are different from medicinal plants which are naturally available.

PCR stands for Polymerase Chain Reaction.
PCR is a common lab technique used to make copies of particular region of DNA.

Bioreactor (Fermenter) is a vessel or a container that is designed in such a way that it can provide an optimum environment in which microorganisms or their enzymes interact with a substrate to produce the required product. In the bioreactor, aeration, agitation, temperature and pH are controlled.

Polyethylene Glycol (PEG) and Dextran Sulphate.

Restriction endonuclease. e.g: Hind II, EcoR I, Pvul, Bam H I, Taq I.

The advantages of Bt cotton are:
1. Yield of cotton is increased due to effective control of bollworms.
2. Reduction in insecticide use in the cultivation of Bt cotton
3. Potential reduction in the cost of cultivation.
Disadvantages
Bt cotton has some limitations:
1. Cost of Bt cotton seed is high.
2. Effectiveness up to 120 days after that efficiency is reduced.
3. Ineffective against sucking pests like jassids, aphids and whitefly.
4. Affects pollinating insects and thus yield.

Properties of Vectors:
1. Vectors are able to replicate autonomously to produce multiple copies of them along with their DNA insert in the host cell.
2. It should be small in size and of low molecular weight, less than 10 Kb (kilo base pair) in size so that entry/transfer into host cell is easy.
3. Vector must contain an origin of replication so that it can independently replicate within the host.
4. It should contain a suitable marker such as antibiotic resistance, to permit its detection in transformed host cell.
5. Vector should have unique target sites for integration with DNA insert and should have the ability to integrate with DNA insert it carries into the genome of the host cell. Most of the commonly used cloning vectors have more than one restriction site. These are Multiple Cloning Site (MCS) or polylinker. Presence of MCS facilitates the use of restriction enzyme of choice.

(i) pBR 322 plasmid is a reconstructed plasmid and most widely used as cloning vector;
(ii) It contains 4361 base pairs. In pBR, p denotes plasmid, Band R respectively the names of scientist Boliver and Rodriguez who developed this plasmid.
(iii) The number 322 is the number of plasmid developed from their laboratory.
(iv) It contains amp^R and tet^R two different antibiotic resistance genes and recognition sites for several restriction enzymes.
(v) ori and antibiotic resistance genes. Rop codes for the proteins involved in the replication of the plasmid.