A Blog for aspirants of Group 1 service in Andhra Pradesh
Showing posts with label Paper 4. Show all posts
Showing posts with label Paper 4. Show all posts
Thursday, September 16, 2010
Threats to biodiversity
What are the Threats to Biodiversity?
Extinction is a natural event and, from a geological perspective, routine. We now know that most species that have ever lived have gone extinct. The average rate over the past 200 my is 1-2 species per year, and 3-4 families per my. The average duration of a species is 2-10 million years (based on last 200 million years). There have also been occasional episodes of mass extinction, when many taxa representing a wide array of lifeforms have gone extinct in the same blink of geological time. [see last Fall's lecture on the Emergence Of Complex Life] In the modern era, due to human actions, species and ecosystems are threatened with destruction to an extent rarely seen in earth history. Probably only during the handful of mass extinction events have so many species been threatened, in so short a time.What are these human actions? There are many ways to conceive of these - let's consider two.
 |
Source: World Conservation Monitoring Centre, "Global Biodiversity" Chapman & Hall, London, 1992). |
Second, we can examine six specific types of human actions that threaten species and ecosystems - the "sinister sextet"
Over-hunting has been a significant cause of the extinction of hundreds of species and the endangerment of many more, such as whales and many African large mammals. Most extinctions over past several hundred years are mainly due to over-harvesting for food, fashion, and profit.  Passenger Pigeons |
|---|
While over-hunting, particularly illegal poaching, remains a serious threat to certain species, for the future, it is less important than other factors mentioned next.
Habitat loss/degradation/fragmentation is an important cause of known extinctions. As deforestation proceeds in tropical forests, this promises to become THE cause of mass extinctions caused by human activity.
All species have specific food and habitat needs. The more specific these needs and localized the habitat, the greater the vulnerability of species to loss of habitat to agricultural land, livestock, roads and cities. In the future, the only species that survive are likely to be those whose habitats are highly protected, or whose habitat corresponds to the degraded state associated with human activity (human commensals).
Habitat damage, especially the conversion of forested land to agriculture (and, often, subsequent abandonment as marginal land), has a long human history. It began in China about 4,000 years ago, was largely completed in Europe by about 400 years ago, and swept across USA over the past 200 years or so. Viewed in this historical context, we are now mopping up the last forests of Pacific Northwest.
In the new world tropics, lowland, seasonal, deciduous forest began to disappear after 1500 with Spanish and Portuguese colonization of the New World. These were the forested regions most easily converted to agriculture, and with a more welcoming climate. The more forbidding, tropical humid forests came under attack mainly in 20th C, under the combined influences of population growth, inequitable land and income distribution, and development policies that targeted rain forests as the new frontier to colonize.
Tropical forests are so important because they harbor at least 50%, and perhaps more, of world's biodiversity. Direct observations, reinforced by satellite data, documents that these forests are declining. The original extent of tropical rain forests was 15 million km2. Now there remains about 7.5-8 million km2, so half is gone. The current rate of loss is estimated at near 2% annually (100,000 km2 destroyed, another 100,000 km2 degraded). While there is uncertainty regarding the rate of loss, and what it will be in future, the likelihood is that tropical forests will be reduced to 10-25% of their original extent by late 21st C. Habitat fragmentation is a further aspect of habitat loss that often goes unrecognized. The forest, meadow, or other habitat that remains generally is in small, isolated bits rather than in large, intact units. Each is a tiny island that can at best mai ntain a very small population. Environmental fluctuations, disease, and other chance factors make such small isolates highly vulnerable to extinction. Any species that requires a large home range, such as a grizzly bear, will not survive if the area is too small. Finally, we know that small land units are strongly affected by their surroundings, in terms of climate, dispersing species, etc. As a consequence, the ecology of a small isolate may differ from that of a similar ecosystem on a larger scale.
For the future, habitat loss, degradation, and fragmentation combined is the single most important factor in the projected extinction crisis.
Invasion of non-native species is an important and often-overlooked cause of extinctions. The African Great Lakes - Victoria, Malawi and Tanganyika - are famous for their great diversity of endemic species, termed "species flocks", of cichlid fishes. In Lake Victoria, a single, exotic species, the Nile Perch, has become established and may cause the extinction of most of the native species, by simply eating them all. It was a purposeful introduction for subsistence and sports fishing, and a great disaster.
Of all documented extinctions since 1600, introduced species appear to have played a role in at least half. The clue is the disproportionate number of species lost from islands: some 93% of 30 documented extinctions of species and sub-species of amphibians and reptiles, 93% of 176 species and sub-species of land and freshwater birds, but only 27% of 114 species and subspecies of mammals. Why are island species so vulnerable, and why is this evidence of the role of non-indigenous species?
Islands are laboratories for evolution ( occur when the removal of one species (an extinction event) or the addition of one species (an invasion event) affects the entire biological system. Domino effects are especially likely when two or more species are highly inter-dependent, or when the affected species is a "keystone" species, meaning that it has strong connections to many other species (GCI).
The seeds of the tree Calvaria major, now found exclusively on the island of Mauritius, must pass through the abrasive gut of a large animal in order to germinate. Their tough seed coats are protection against digestion, but also a kind of living coffin, for the seed can not germinate unless abraded. None of the animals currently on Mauritius have that ability. The dodo (a 25 kg pigeon), hunted to extinction in the late 17th century, probably was the key to recruitment in this species. Some seeds, abraded, roughened, and excreted by dodos, germinated and grew. Today, no seeds germinate, and only a few very old trees now survive. The blackfooted ferret was once very abundant in the western prairies. It preyed upon prairie dogs and used their burrows to nest in. Poisoning of prairie dogs has greatly reduced their abundance, and the blackfooted ferret is now the rarest mammal in North America
Pollution from chemical contaminants certainly poses a further threat to species and ecosystems. While not commonly a cause of extinction, it likely can be for species whose range is extremely small, and threatened by contamination. Several species of desert pupfish, occurring in small isolated pools in the US southwest, are examples.
Climate change: A changing global climate threatens species and ecosystems. The distribution of species (biogeography) is largely determined by climate, as is the distribution of ecosystems and plant vegetation zones (biomes) [GCI]. Climate change may simply shift these distributions but, for a number of reasons, plants and animals may not be able to adjust.
The pace of climate change almost certainly will be more rapid than most plants are able to migrate The presence of roads, cities, and other barriers associated with human presence may provide no opportunity for distributional shifts. Parks and nature reserves are fixed locations. The climate that characterizes present-day Yellowstone Park will shift several hundred miles northward. The park itself is a fixed location. For these reasons, some species and ecosystems are likely to be eliminated by climate change. Agricultural production likely will show regional variation in gains and losses, depending upon crop and climate.
As a consequence of these multiple forces, many scientists fear that by end of next century, perhaps 25% of existing species will be lost.
Biodiversity
1. What is Biodiversity?
What is biological diversity ? In its narrowest sense this term refers to the number of species on the planet, and it also is used more broadly as an umbrella term. Biological diversity refers to the variety and variability among living organisms and the ecological complexes in which they occur. Diversity can be defined as the number of different items and their relative frequency. For biological diversity, these items are organized at many levels, ranging from complete ecosystems to the chemical structures that are the molecular basis of heredity. Thus, the term encompasses different ecosystems, species, genes, and their relative abundance (Office of Technology Assessment, 1987). Or to paraphrase: number and variety of species, ecological systems, and the genetic variability they contain.The simplest representation is:
| Group | Number of Described Species |
| Bacteria and blue-green algae | 4,760 |
| Fungi | 46,983 |
| Algae | 26,900 |
| Bryophytes (mosses and liverworts) | 17,000 |
| Gymnosperms (conifers) | 750 |
| Angiosperms (flowering plants) | 250,000 |
| Protozoans | 30,800 |
| Sponges | 5,000 |
| Corals and Jellyfish | 9,000 |
| Roundworms and earthworms | 24,000 |
| Crustaceans | 38,000 |
| Insects | 751,000 |
| Other Arthropods and minor invertebrates | 132,461 |
| Mollusks | 50,000 |
| Starfish | 6,100 |
| Fishes (teleosts) | 19,056 |
| Amphibians | 4,184 |
| Reptiles | 6,300 |
| Birds | 9,198 |
| Mammals | 4,170 |
Total | 1,435,662 |
Remarkably, our estimates of the number of unknown species greatly exceed our count of the number of known species. Most experts estimate the world's species diversity at 10 to 30 million, but that is very approximate. Only 1.4 million species are "known to science" -- meaning that they have been classified by a specialist. The estimates of 10 to 30 million species are based on expert opinion of how many species are yet to be formally identified. One study of insects in the forest canopy found 5 out of 6 to be new species. Even vertebrates are not completely known -- it is estimated that nearly half of the freshwater fishes of South America are undescribed. New finds are made continuously in the tropics, and exploration of deep-sea hydrothermal vents recently led to the discovery not just of new species, but of new life forms at the family level (20 families or sub-families). When you consider that virtually every species has its own parasite, and how many groups such as nematodes and bacteria have yet to be well-studied, it is apparent that the estimates of 10 to 30 million are not out of line.
The global distribution of biodiversity -- its geography -- is interesting in its own right, and relevant to conservation. Biological diversity is greatest near the equator, and declines towards higher latitudes . Tropical rain forests are especially known for their exceptional diversity. Some locations known as "hotspots" harbour an unusually rich local diversity, perhaps because conditions favour evolutionary diversification.
Friday, October 23, 2009
Transgenic Animal - Production and Applications
Nowadays, breakthroughs in molecular biology are happening at an unprecedented rate. One of them is the ability to engineer transgenic animals, i.e., animals that carry genes from other species. The technology has already produced transgenic animals such as mice, rats, rabbits, pigs, sheep, and cows. Although there are many ethical issues surrounding transgenesis, this article focuses on the basics of the technology and its applications in agriculture, medicine, and industry.
What is a transgenic animal?
There are various definitions for the term transgenic animal. The Federation of European Laboratory Animal Associations defines the term as an animal in which there has been a deliberate modification of its genome, the genetic makeup of an organism responsible for inherited characteristics.
The nucleus of all cells in every living organism contains genes made up of DNA. These genes store information that regulates how our bodies form and function. Genes can be altered artificially, so that some characteristics of an animal are changed. For example, an embryo can have an extra, functioning gene from another source artificially introduced into it, or a gene introduced which can knock out the functioning of another particular gene in the embryo. Animals that have their DNA manipulated in this way are knows as transgenic animals.
The majority of transgenic animals produced so far are mice, the animal that pioneered the technology. The first successful transgenic animal was a mouse. A few years later, it was followed by rabbits, pigs, sheep, and cattle.
Why are these animals being produced? The two most common reasons are:
* Some transgenic animals are produced for specific economic traits. For example, transgenic cattle were created to produce milk containing particular human proteins, which may help in the treatment of human emphysema.
* Other transgenic animals are produced as disease models (animals genetically manipulated to exhibit disease symptoms so that effective treatment can be studied). For example, Harvard scientists made a major scientific breakthrough when they received a U.S. patent (the company DuPont holds exclusive rights to its use) for a genetically engineered mouse, called OncoMouse® or the Harvard mouse, carrying a gene that promotes the development of various human cancers.
How are transgenic animals produced?
Since the discovery of the molecular structure of DNA by Watson and Crick in 1953, molecular biology research has gained momentum. Molecular biology technology combines techniques and expertise from biochemistry, genetics, cell biology, developmental biology, and microbiology.
Scientists can now produce transgenic animals because, since Watson and Crick’s discovery, there have been breakthroughs in:
* recombinant DNA (artificially-produced DNA)
* genetic cloning
* analysis of gene expression (the process by which a gene gives rise to a protein)
* genomic mapping
The underlying principle in the production of transgenic animals is the introduction of a foreign gene or genes into an animal (the inserted genes are called transgenes). The foreign genes “must be transmitted through the germ line, so that every cell, including germ cells, of the animal contain the same modified genetic material.” (Germ cells are cells whose function is to transmit genes to an organism’s offspring.)
To date, there are three basic methods of producing transgenic animals:
* DNA microinjection
* Retrovirus-mediated gene transfer
* Embryonic stem cell-mediated gene transfer
Gene transfer by microinjection is the predominant method used to produce transgenic farm animals. Since the insertion of DNA results in a random process, transgenic animals are mated to ensure that their offspring acquire the desired transgene. However, the success rate of producing transgenic animals individually by these methods is very low and it may be more efficient to use cloning techniques to increase their numbers. For example, gene transfer studies revealed that only 0.6% of transgenic pigs were born with a desired gene after 7,000 eggs were injected with a specific transgene.
1. DNA Microinjection
The mouse was the first animal to undergo successful gene transfer using DNA microinjection. This method involves:
* transfer of a desired gene construct (of a single gene or a combination of genes that are recombined and then cloned) from another member of the same species or from a different species into the pronucleus of a reproductive cell
* the manipulated cell, which first must be cultured in vitro (in a lab, not in a live animal) to develop to a specific embryonic phase, is then transferred to the recipient female
2. Retrovirus-Mediated Gene Transfer
A retrovirus is a virus that carries its genetic material in the form of RNA rather than DNA. This method involves:
* retroviruses used as vectors to transfer genetic material into the host cell, resulting in a chimera, an organism consisting of tissues or parts of diverse genetic constitution
* chimeras are inbred for as many as 20 generations until homozygous (carrying the desired transgene in every cell) transgenic offspring are born
The method was successfully used in 1974 when a simian virus was inserted into mice embryos, resulting in mice carrying this DNA.
3. Embryonic Stem Cell-Mediated Gene Transfer
This method involves:
* isolation of totipotent stem cells (stem cells that can develop into any type of specialized cell) from embryos
* the desired gene is inserted into these cells
* cells containing the desired DNA are incorporated into the host’s embryo, resulting in a chimeric animal
Unlike the other two methods, which require live transgenic offspring to test for the presence of the desired transgene, this method allows testing for transgenes at the cell stage.
How do transgenic animals contribute to human welfare?
The benefits of these animals to human welfare can be grouped into areas:
* Agriculture
* Medicine
* Industry
The examples below are not intended to be complete but only to provide a sampling of the benefits.
1. Agricultural Applications
a) breeding
Farmers have always used selective breeding to produce animals that exhibit desired traits (e.g., increased milk production, high growth rate). Traditional breeding is a time-consuming, difficult task. When technology using molecular biology was developed, it became possible to develop traits in animals in a shorter time and with more precision. In addition, it offers the farmer an easy way to increase yields.
b) quality
Transgenic cows exist that produce more milk or milk with less lactose or cholesterol, pigs and cattle that have more meat on them, and sheep that grow more wool18. In the past, farmers used growth hormones to spur the development of animals but this technique was problematic, especially since residue of the hormones remained in the animal product.
c) disease resistance
Scientists are attempting to produce disease-resistant animals, such as influenza-resistant pigs, but a very limited number of genes are currently known to be responsible for resistance to diseases in farm animals.
2. Medical Applications
a) xenotransplantation
Patients die every year for lack of a replacement heart, liver, or kidney. For example, about 5,000 organs are needed each year in the United Kingdom alone.25 Transgenic pigs may provide the transplant organs needed to alleviate the shortfall. Currently, xenotransplantation is hampered by a pig protein that can cause donor rejection but research is underway to remove the pig protein and replace it with a human protein.
b) nutritional supplements and pharmaceuticals
Products such as insulin, growth hormone, and blood anti-clotting factors may soon be or have already been obtained from the milk of transgenic cows, sheep, or goats.3,12,23 Research is also underway to manufacture milk through transgenesis for treatment of debilitating diseases such as phenylketonuria (PKU), hereditary emphysema, and cystic fibrosis.
In 1997, the first transgenic cow, Rosie, produced human protein-enriched milk at 2.4 grams per litre. This transgenic milk is a more nutritionally balanced product than natural bovine milk and could be given to babies or the elderly with special nutritional or digestive needs. Rosie’s milk contains the human gene alpha-lactalbumin.
c) human gene therapy
Human gene therapy involves adding a normal copy of a gene (transgene) to the genome of a person carrying defective copies of the gene. The potential for treatments for the 5,000 named genetic diseases is huge and transgenic animals could play a role. For example, the A. I. Virtanen Institute in Finland produced a calf with a gene that makes the substance that promotes the growth of red cells in humans.
3. Industrial Applications
In 2001, two scientists at Nexia Biotechnologies in Canada spliced spider genes into the cells of lactating goats. The goats began to manufacture silk along with their milk and secrete tiny silk strands from their body by the bucketful. By extracting polymer strands from the milk and weaving them into thread, the scientists can create a light, tough, flexible material that could be used in such applications as military uniforms, medical microsutures, and tennis racket strings.
Toxicity-sensitive transgenic animals have been produced for chemical safety testing. Microorganisms have been engineered to produce a wide variety of proteins, which in turn can produce enzymes that can speed up industrial chemical reactions.
What are the ethical concerns surrounding transgenesis?
This article focuses on the benefits of the technology; however, thoughtful ethical decision-making cannot be ignored by the biotechnology industry, scientists, policy-makers, and the public. These ethical issues, better served in their own article, include questions such as:
* Should there be universal protocols for transgenesis?
* Should such protocols demand that only the most promising research be permitted?
* Is human welfare the only consideration? What about the welfare of other life forms?
* Should scientists focus on in vitro (cultured in a lab) transgenic methods rather than, or before, using live animals to alleviate animal suffering?
* Will transgenic animals radically change the direction of evolution, which may result in drastic consequences for nature and humans alike?
* Should patents be allowed on transgenic animals, which may hamper the free exchange of scientific research?
Conclusion
Interestingly, the creation of transgenic animals has resulted in a shift in the use of laboratory animals — from the use of higher-order species such as dogs to lower-order species such as mice — and has decreased the number of animals used in such experimentation, especially in the development of disease models. This is certainly a good turn of events since transgenic technology holds great potential in many fields, including agriculture, medicine, and industry.
What is a transgenic animal?
There are various definitions for the term transgenic animal. The Federation of European Laboratory Animal Associations defines the term as an animal in which there has been a deliberate modification of its genome, the genetic makeup of an organism responsible for inherited characteristics.
The nucleus of all cells in every living organism contains genes made up of DNA. These genes store information that regulates how our bodies form and function. Genes can be altered artificially, so that some characteristics of an animal are changed. For example, an embryo can have an extra, functioning gene from another source artificially introduced into it, or a gene introduced which can knock out the functioning of another particular gene in the embryo. Animals that have their DNA manipulated in this way are knows as transgenic animals.
The majority of transgenic animals produced so far are mice, the animal that pioneered the technology. The first successful transgenic animal was a mouse. A few years later, it was followed by rabbits, pigs, sheep, and cattle.
Why are these animals being produced? The two most common reasons are:
* Some transgenic animals are produced for specific economic traits. For example, transgenic cattle were created to produce milk containing particular human proteins, which may help in the treatment of human emphysema.
* Other transgenic animals are produced as disease models (animals genetically manipulated to exhibit disease symptoms so that effective treatment can be studied). For example, Harvard scientists made a major scientific breakthrough when they received a U.S. patent (the company DuPont holds exclusive rights to its use) for a genetically engineered mouse, called OncoMouse® or the Harvard mouse, carrying a gene that promotes the development of various human cancers.
How are transgenic animals produced?
Since the discovery of the molecular structure of DNA by Watson and Crick in 1953, molecular biology research has gained momentum. Molecular biology technology combines techniques and expertise from biochemistry, genetics, cell biology, developmental biology, and microbiology.
Scientists can now produce transgenic animals because, since Watson and Crick’s discovery, there have been breakthroughs in:
* recombinant DNA (artificially-produced DNA)
* genetic cloning
* analysis of gene expression (the process by which a gene gives rise to a protein)
* genomic mapping
The underlying principle in the production of transgenic animals is the introduction of a foreign gene or genes into an animal (the inserted genes are called transgenes). The foreign genes “must be transmitted through the germ line, so that every cell, including germ cells, of the animal contain the same modified genetic material.” (Germ cells are cells whose function is to transmit genes to an organism’s offspring.)
To date, there are three basic methods of producing transgenic animals:
* DNA microinjection
* Retrovirus-mediated gene transfer
* Embryonic stem cell-mediated gene transfer
Gene transfer by microinjection is the predominant method used to produce transgenic farm animals. Since the insertion of DNA results in a random process, transgenic animals are mated to ensure that their offspring acquire the desired transgene. However, the success rate of producing transgenic animals individually by these methods is very low and it may be more efficient to use cloning techniques to increase their numbers. For example, gene transfer studies revealed that only 0.6% of transgenic pigs were born with a desired gene after 7,000 eggs were injected with a specific transgene.
1. DNA Microinjection
The mouse was the first animal to undergo successful gene transfer using DNA microinjection. This method involves:
* transfer of a desired gene construct (of a single gene or a combination of genes that are recombined and then cloned) from another member of the same species or from a different species into the pronucleus of a reproductive cell
* the manipulated cell, which first must be cultured in vitro (in a lab, not in a live animal) to develop to a specific embryonic phase, is then transferred to the recipient female
2. Retrovirus-Mediated Gene Transfer
A retrovirus is a virus that carries its genetic material in the form of RNA rather than DNA. This method involves:
* retroviruses used as vectors to transfer genetic material into the host cell, resulting in a chimera, an organism consisting of tissues or parts of diverse genetic constitution
* chimeras are inbred for as many as 20 generations until homozygous (carrying the desired transgene in every cell) transgenic offspring are born
The method was successfully used in 1974 when a simian virus was inserted into mice embryos, resulting in mice carrying this DNA.
3. Embryonic Stem Cell-Mediated Gene Transfer
This method involves:
* isolation of totipotent stem cells (stem cells that can develop into any type of specialized cell) from embryos
* the desired gene is inserted into these cells
* cells containing the desired DNA are incorporated into the host’s embryo, resulting in a chimeric animal
Unlike the other two methods, which require live transgenic offspring to test for the presence of the desired transgene, this method allows testing for transgenes at the cell stage.
How do transgenic animals contribute to human welfare?
The benefits of these animals to human welfare can be grouped into areas:
* Agriculture
* Medicine
* Industry
The examples below are not intended to be complete but only to provide a sampling of the benefits.
1. Agricultural Applications
a) breeding
Farmers have always used selective breeding to produce animals that exhibit desired traits (e.g., increased milk production, high growth rate). Traditional breeding is a time-consuming, difficult task. When technology using molecular biology was developed, it became possible to develop traits in animals in a shorter time and with more precision. In addition, it offers the farmer an easy way to increase yields.
b) quality
Transgenic cows exist that produce more milk or milk with less lactose or cholesterol, pigs and cattle that have more meat on them, and sheep that grow more wool18. In the past, farmers used growth hormones to spur the development of animals but this technique was problematic, especially since residue of the hormones remained in the animal product.
c) disease resistance
Scientists are attempting to produce disease-resistant animals, such as influenza-resistant pigs, but a very limited number of genes are currently known to be responsible for resistance to diseases in farm animals.
2. Medical Applications
a) xenotransplantation
Patients die every year for lack of a replacement heart, liver, or kidney. For example, about 5,000 organs are needed each year in the United Kingdom alone.25 Transgenic pigs may provide the transplant organs needed to alleviate the shortfall. Currently, xenotransplantation is hampered by a pig protein that can cause donor rejection but research is underway to remove the pig protein and replace it with a human protein.
b) nutritional supplements and pharmaceuticals
Products such as insulin, growth hormone, and blood anti-clotting factors may soon be or have already been obtained from the milk of transgenic cows, sheep, or goats.3,12,23 Research is also underway to manufacture milk through transgenesis for treatment of debilitating diseases such as phenylketonuria (PKU), hereditary emphysema, and cystic fibrosis.
In 1997, the first transgenic cow, Rosie, produced human protein-enriched milk at 2.4 grams per litre. This transgenic milk is a more nutritionally balanced product than natural bovine milk and could be given to babies or the elderly with special nutritional or digestive needs. Rosie’s milk contains the human gene alpha-lactalbumin.
c) human gene therapy
Human gene therapy involves adding a normal copy of a gene (transgene) to the genome of a person carrying defective copies of the gene. The potential for treatments for the 5,000 named genetic diseases is huge and transgenic animals could play a role. For example, the A. I. Virtanen Institute in Finland produced a calf with a gene that makes the substance that promotes the growth of red cells in humans.
3. Industrial Applications
In 2001, two scientists at Nexia Biotechnologies in Canada spliced spider genes into the cells of lactating goats. The goats began to manufacture silk along with their milk and secrete tiny silk strands from their body by the bucketful. By extracting polymer strands from the milk and weaving them into thread, the scientists can create a light, tough, flexible material that could be used in such applications as military uniforms, medical microsutures, and tennis racket strings.
Toxicity-sensitive transgenic animals have been produced for chemical safety testing. Microorganisms have been engineered to produce a wide variety of proteins, which in turn can produce enzymes that can speed up industrial chemical reactions.
What are the ethical concerns surrounding transgenesis?
This article focuses on the benefits of the technology; however, thoughtful ethical decision-making cannot be ignored by the biotechnology industry, scientists, policy-makers, and the public. These ethical issues, better served in their own article, include questions such as:
* Should there be universal protocols for transgenesis?
* Should such protocols demand that only the most promising research be permitted?
* Is human welfare the only consideration? What about the welfare of other life forms?
* Should scientists focus on in vitro (cultured in a lab) transgenic methods rather than, or before, using live animals to alleviate animal suffering?
* Will transgenic animals radically change the direction of evolution, which may result in drastic consequences for nature and humans alike?
* Should patents be allowed on transgenic animals, which may hamper the free exchange of scientific research?
Conclusion
Interestingly, the creation of transgenic animals has resulted in a shift in the use of laboratory animals — from the use of higher-order species such as dogs to lower-order species such as mice — and has decreased the number of animals used in such experimentation, especially in the development of disease models. This is certainly a good turn of events since transgenic technology holds great potential in many fields, including agriculture, medicine, and industry.
Thursday, October 22, 2009
Amendments to Article 243 T of the Constitution for enhancing reservation for women in Urban Local Bodies to 50 percent
The Union Cabinet today approved the proposal for moving a Constitutional Amendment Bill for enhancing reservation for women in Urban Local Bodies from one third to fifty percent. This provision will apply to (i) the total number of seats to be filled by direct election, (ii) offices of Chairpersons and (iii) seats and offices of the Chairpersons reserved for SCs and STs.
Increased representation of women is likely to yield significant benefits in terms of higher priority to women’s issues in critical areas of urban Governance and service delivery such as water supply, sanitation, solid waste management, education and health etc.
BACKGROUND :
The President of India in her address to the Parliament on 4.6.09 stated that the Government will initiate steps for Constitutional Amendment to provide fifty percent reservation for women in Urban Local Bodies as women suffer multiple deprivations of class, caste and gender and enhancing reservation in Urban Local Bodies will lead to more women entering the public sphere.
Implementation Strategy & Targets
Ministry of Urban Development will move a Bill for amendment to Article 243 T of the Constitution in the next session of Parliament after approval of the Cabinet.
Major Impact
Enhancement of reservation for women in Urban Local Bodies will not only ensure their increased representation and participation at grassroots levels in various Urban Local Bodies but also mainstream gender concerns in governance and decision making process.
Expenditure involved
There is no financial implication in operationalization of the proposal.
States/Districts covered
The proposed Constitution Amendment Bill would cover All States/UTs and parts thereof, which are covered by Part IX A of Constitution.
Increased representation of women is likely to yield significant benefits in terms of higher priority to women’s issues in critical areas of urban Governance and service delivery such as water supply, sanitation, solid waste management, education and health etc.
BACKGROUND :
The President of India in her address to the Parliament on 4.6.09 stated that the Government will initiate steps for Constitutional Amendment to provide fifty percent reservation for women in Urban Local Bodies as women suffer multiple deprivations of class, caste and gender and enhancing reservation in Urban Local Bodies will lead to more women entering the public sphere.
Implementation Strategy & Targets
Ministry of Urban Development will move a Bill for amendment to Article 243 T of the Constitution in the next session of Parliament after approval of the Cabinet.
Major Impact
Enhancement of reservation for women in Urban Local Bodies will not only ensure their increased representation and participation at grassroots levels in various Urban Local Bodies but also mainstream gender concerns in governance and decision making process.
Expenditure involved
There is no financial implication in operationalization of the proposal.
States/Districts covered
The proposed Constitution Amendment Bill would cover All States/UTs and parts thereof, which are covered by Part IX A of Constitution.
GM research is needed urgently to avoid food crisis, says Royal Society
Research to develop genetically modified crops must be stepped up as part of a £2bn "grand challenge" to avoid future food shortages, an influential panel of scientists said yesterday. In its report, the Royal Society said that GM techniques would be needed to boost yields and help crops survive harsher climates, as the global population rises and global warming worsens.
But the report said GM was not the only answer, and that measures to improve crop management, such as improved irrigation, were needed too.
Professor David Baulcombe, a plant scientist at the University of Cambridge who chaired the study, said: "We need to take action now to stave off food shortages. If we wait even five to 10 years, it may be too late. Biological science has progressed in leaps and bounds in the last decade and UK scientists have been at the head of the pack when it comes to topics related to food crops. In the UK we have the potential to come up with viable scientific solutions for feeding a growing population and we have a responsibility to realise this potential. There's a very clear need for policy action and publicly funded science to make sure this happens."
The Royal Society said the government should reverse a decay in agricultural research in Britain and spend at least £200m each year for the next 10 years on science that improves crops and sustainable crop management.
The report said the changing diets of people around the world, the likely impact of climate change and growing scarcity of water and land made it harder to increase food production to meet an expected rise in global population of 3 billion by the mid-century. Production methods would need to sustain the environment, preserve natural resources and support the livelihoods of farmers and rural populations around the world, it added.
The report came as John Beddington, chief scientific adviser to the government, said a "range of solutions" would be needed to feed a growing world population.
Baulcombe added: "There is no panacea for ensuring global food security. Science-based approaches introduced alongside social science and economic innovations are essential if we're to have a decent chance of feeding the world's population in 40 years' time. Technologies that work on a farm in the UK may have little impact for harvests in Africa. Research is going to need to take into account a diverse range of crops, localities, cultures and numerous other circumstances."
Anti-GM campaigners criticised the report, which they said was at odds with a separate report on future food production produced last year by the International Assessment of Agricultural Science and Technology for Development (IAASTD), which said there was little role for GM, as currently practised, in feeding the poor on a large scale.
Kirtana Chandrasekaran of Friends of the Earth said: "Science has a key role to play in reducing hunger and poverty, but the report's focus on GM crops ignores mounting evidence that this technology is failing. GM crops are an extension of big-business factory farming that is already wiping out wildlife, destroying communities and making climate change worse. Any attempt to combat the global food crisis must also address its root causes, such as industrial livestock production and a narrow focus on increasing yields."
Tom MacMillan, executive director of the Food Ethics Council, said: "They get ahead of themselves by demanding £2bn more for science. That's exactly the kind of decision that should be up for wider debate. The money might be better spent tackling the social and economic problems that affect whether growing more food makes a jot of difference to food security."
Julian Little, chairman of the Agricultural Biotechnology Council, which represents GM crop companies, said: "Farmers must be given access to all the proven tools available to help them produce more food in a more sustainable way. This should include advanced crop breeding using biotechnology and GM methods, which are already being used by more than 13 million farmers around the world and helping to deliver higher and more reliable crop yields while mitigating major threats to crop production, such as damaging effects of pests, diseases and droughts."
But the report said GM was not the only answer, and that measures to improve crop management, such as improved irrigation, were needed too.
Professor David Baulcombe, a plant scientist at the University of Cambridge who chaired the study, said: "We need to take action now to stave off food shortages. If we wait even five to 10 years, it may be too late. Biological science has progressed in leaps and bounds in the last decade and UK scientists have been at the head of the pack when it comes to topics related to food crops. In the UK we have the potential to come up with viable scientific solutions for feeding a growing population and we have a responsibility to realise this potential. There's a very clear need for policy action and publicly funded science to make sure this happens."
The Royal Society said the government should reverse a decay in agricultural research in Britain and spend at least £200m each year for the next 10 years on science that improves crops and sustainable crop management.
The report said the changing diets of people around the world, the likely impact of climate change and growing scarcity of water and land made it harder to increase food production to meet an expected rise in global population of 3 billion by the mid-century. Production methods would need to sustain the environment, preserve natural resources and support the livelihoods of farmers and rural populations around the world, it added.
The report came as John Beddington, chief scientific adviser to the government, said a "range of solutions" would be needed to feed a growing world population.
Baulcombe added: "There is no panacea for ensuring global food security. Science-based approaches introduced alongside social science and economic innovations are essential if we're to have a decent chance of feeding the world's population in 40 years' time. Technologies that work on a farm in the UK may have little impact for harvests in Africa. Research is going to need to take into account a diverse range of crops, localities, cultures and numerous other circumstances."
Anti-GM campaigners criticised the report, which they said was at odds with a separate report on future food production produced last year by the International Assessment of Agricultural Science and Technology for Development (IAASTD), which said there was little role for GM, as currently practised, in feeding the poor on a large scale.
Kirtana Chandrasekaran of Friends of the Earth said: "Science has a key role to play in reducing hunger and poverty, but the report's focus on GM crops ignores mounting evidence that this technology is failing. GM crops are an extension of big-business factory farming that is already wiping out wildlife, destroying communities and making climate change worse. Any attempt to combat the global food crisis must also address its root causes, such as industrial livestock production and a narrow focus on increasing yields."
Tom MacMillan, executive director of the Food Ethics Council, said: "They get ahead of themselves by demanding £2bn more for science. That's exactly the kind of decision that should be up for wider debate. The money might be better spent tackling the social and economic problems that affect whether growing more food makes a jot of difference to food security."
Julian Little, chairman of the Agricultural Biotechnology Council, which represents GM crop companies, said: "Farmers must be given access to all the proven tools available to help them produce more food in a more sustainable way. This should include advanced crop breeding using biotechnology and GM methods, which are already being used by more than 13 million farmers around the world and helping to deliver higher and more reliable crop yields while mitigating major threats to crop production, such as damaging effects of pests, diseases and droughts."
Wednesday, October 21, 2009
Paper 4 - Section 2- Chapter 3... imp questions
1. What are stem cells? what are different types of stem cells
What are the uses and write about research if stem cells in national and international level
2. What are bio fuels? Types of bio fuels. Write about its development and usage in India. write about national bio fuel program
3. What is genetic engineering? Methods of genetic engineering. what are the characteristics of genetic engineering?
4. Role of bio fertilizers and bio pesticides in agriculture and their use in India today?
5. What is tissue culture? Process of tissue culture? characteristics of
6. What are the methods used for production of transgenic animals? characteristics of them?
7. Role of bio technology in agriculture?
What are the uses and write about research if stem cells in national and international level
2. What are bio fuels? Types of bio fuels. Write about its development and usage in India. write about national bio fuel program
3. What is genetic engineering? Methods of genetic engineering. what are the characteristics of genetic engineering?
4. Role of bio fertilizers and bio pesticides in agriculture and their use in India today?
5. What is tissue culture? Process of tissue culture? characteristics of
6. What are the methods used for production of transgenic animals? characteristics of them?
7. Role of bio technology in agriculture?
Wednesday, September 16, 2009
APPSC Papers 2008
Below are the links of question papers of Group one exam conducted in 2008. I am giving the links paper wise. I am trying to locate model question papers provided by APPSC before this exam. Though I have a paper copy I am trying to locate a e-copy of those papers and also prelims paper. Once I identify them I will notify here.
PAPER 1
PAPER 2
PAPER 3
PAPER 4
PAPER 5
GENERAL ENGLISH
Hope this will be helpful.
PAPER 1
PAPER 2
PAPER 3
PAPER 4
PAPER 5
GENERAL ENGLISH
Hope this will be helpful.
My Plan of preperation
Hi.. I will be uploading details as per the way I prepare and material I collect since it is not my own material or concepts almost every material will be from some source. I only keep them at one place here so that it will be a one point junction for all preparation material. You can ask me any doubts and clarifications in this matter.
As of now I am preparing for Paper 3 and Paper 5 for mains along with prelims. So we shall be having material and discussion on this areas particularly.
My findings will be pin point and will have information from examination point of view since our aim is to write stuff of 200 words with in given 10 minutes for a question with utmost matter we know. There should be no question of checking for words or answers while writing it.stick to the question and answer it.
As of now I am preparing for Paper 3 and Paper 5 for mains along with prelims. So we shall be having material and discussion on this areas particularly.
My findings will be pin point and will have information from examination point of view since our aim is to write stuff of 200 words with in given 10 minutes for a question with utmost matter we know. There should be no question of checking for words or answers while writing it.stick to the question and answer it.
Subscribe to:
Posts (Atom)