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Showing posts with label UKPSC(Mains) - Paper 6. Show all posts
Showing posts with label UKPSC(Mains) - Paper 6. Show all posts

Tuesday, 5 May 2015

Paper 6 - General Science and Technology

Environmental Problems and Disaster Management
Syllabus - Types of pollution and their management; air, water, soil, sound/noise, radioactive and e-waste. Industrial waste and its management. Impact of Solid Waste Management, recycling and reuse, Watershed Management, Watershed approach for sustainable development, Human role in pollution control, Environment and human health; Effects of pollutants on animals and plants; urbanisation and industrial development.
Global Environmental Issues like Green House Effect, Green House Gases and their mitigation. Climate Change, Acid Rain, Global Warming, Ozone depletion, Biodiversity and its conservation, Hotspots and threats to Biodiversity. The Environment (Protection) Act(1986) and Forest Conservation Act; Kyoto Protocol, Carbon Credits and Carbon Footprint; United Nations Environmental Conservation Programme (UNEP), National parks, Sanctuaries, Biosphere reserves and Botanical gardens; Wildlife and its management, human and wild animal struggle; Seismic activity zones; Development and environment;
Disaster Management: Definition, nature, types and classification of disasters, Natural Hazards; Causative factors and mitigation measures; Disaster Management Act(2005), National Disaster Management Authorities(NDMA);

Environmental Management by Pollution Prevention

Environmental Pollution is defined as presence of harmful concentration of any substances or energy liable to harm to living organisms, comfort resources and ecological damage to structure, amenity or interfere with the legitimate use of environment. Environmental pollution is growing with the advancement of human civilization.
Any substance which causes Environmental pollution is called as environmental pollutant, environmental pollutants include any chemical or geochemical (dust, sediment, grit, etc) substance, biotic component or its product, or physical factor (heat) that is released into the environment in such a concentration that may have adverse or unpleasant effects on environment. A pollutant may also be defined as any solid, liquid or gaseous matter present in such concentration as may be or tend to be harmful to the environment.
Pollutants may be metals, organic and inorganic compounds from domestic and industrial wastes or solid waste, radio-active waste from nuclear plants, heat from thermal power plants, gaseous matter like Carbon monoxide, Oxides of Sulphur, Oxides of Nitrogen (CO,SOx , NOx ). Many Pollutants are the residues of things we make use and throw away. Sources of pollutants are wastes such domestic, industrial and agricultural wastewater. Surface water such as the lakes and rivers are polluted by liquid wastes from chemical and other factories. Atmospheric air is polluted by gases of automobile exhausts, and emissions from industries, thermal power plants, etc.
Wastes containing pollutants produced by a variety of human activities enter the environment either as emissions to atmosphere or discharges to water bodies or land. These pollutants change the natural composition of the environment and adversely affect human beings, animals, plants and material objects.

Pollution Prevention
Pollution prevention may be defined as source reduction, and other practices that reduce or eliminate the creation of pollutants through:

  • increased efficiency in the use of raw materials, energy, water or other resources, or 
  • protection of natural resources by conservation  
Source reduction means any practice which:
  • reduces the amount of any hazardous substance, pollutant, or contaminant entering any waste stream or otherwise released into the environment (including fugitive emissions) prior to recycling, treatment, or disposal; and 
  • reduces the hazards to public health and the environment associated with the release of such substances, pollutants, or contaminants.
Pollution prevention is the best way to protect the environment. It focuses on ways to avoid creating the pollution at its source, before it needs to be cleaned up. This can be done by using less polluting materials in manufacturing, being careful to prevent spills, maintaining equipment in top condition, and through a number of cost-effective techniques. 
Traditionally, programmes have focused on treating or cleaning up pollution after it happens. Pollution prevention means reducing waste at the source by changing the process so that less pollution is created. This is a better approach because it avoids creating the pollution in the first place so that it doesn’t need to be cleaned up. Pollution prevention is voluntary because it goes beyond just complying with environmental regulations.
Common pollution prevention measures include:
  • using less polluting materials in manufacturing,
  • being careful to prevent spills, 
  • maintaining equipment in good condition, 
  • reformulation or redesign of products, 
  • equipment or technology modifications, 
  • processor procedure modifications, and 
  • improvements in house keeping, maintenance, training, or inventory control
Pollution prevention has the following benefits:
  • It protects our environment by avoiding or minimizing the creation of pollution. 
  • Preventing pollution up front avoids costly clean-up, treatment and disposal costs. Usually, companies can save money when they prevent pollution. Sometimes there are costs to get started but these are usually made up by the avoided costs of waste treatment and disposal. 
  • Pollution prevention reduces non-compliance and liability risks, enhances worker’s safety and improves a facility’s image and credibility. 
  • Preventing pollution also minimizes health risks to members of the community.
Pollution Prevention Measures
Make pollution prevention a part of your everyday life! Think of ways to reduce your waste so you can avoid creating pollution. Reuse materials what you can as many times as possible (i.e., lunch bags, reusable containers, cloth napkins). Walk, car pool or ride your bike when possible when you move around. Use environmentally preferable or non-toxic products. 
Many products, such as fluorescent lamps, medical equipment, thermometers and laboratory chemicals, contain mercury. It can enter the air, water or land if these products are disposed of improperly. Mercury bioaccumulates and persists in the environment. It is toxic to humans and wildlife in all of its forms (both organic and inorganic) and can move up the food chain. 
Mercury in the environment can be reduced by using alternative products that don’t contain mercury, cleaning up spills properly, recycling mercury-containing products and properly handling and disposing of mercury-containing equipment.
Environmental Audit may be conducted annually to determine whether its own facilities are in compliance with environmental laws and regulations. 
Pollution prevention approaches can be applied to all pollution-generating activities, including those found in the energy, agriculture, consumer as well as industrial sectors. The impairment of wetlands, ground water sources, and other critical resources constitutes pollution, and prevention practices may be essential for preserving these resources. These practices may include conservation techniques and changes in management practices to prevent harm to sensitive ecosystems. Pollution prevention does not include practices that create new risks of concern.
In the agricultural sector, pollution prevention approaches include:
  • reducing the use of water and chemical inputs; 
  • adoption of less environmentally harmful pesticides or cultivation of crop strains with natural resistance to pests; and 
  • protection of sensitive areas
In the energy sector , pollution prevention can reduce environmental damages from extraction, processing, transport and combustion of fuels. Pollution prevention approaches include:
  • increasing efficiency in energy use; 
  • substituting environmentally benign fuel sources; and 
  • design changes that reduce the demand for energy.
Some practices commonly described as “in-process recycling’ may qualify as pollution prevention. Recycling that is conducted in an environmentally sound manner shares many of the advantages of prevention – it can reduce the need for treatment or disposal and conserve energy and resources.
Remaining competitive in the 21st century requires any business or organization to use pollution prevention strategies that maximize production efficiency and minimize waste.

Cleaner Production Application
Cleaner production (CP) refers to the continuous application of an integrated preventive environmental and business strategy to procure resources, process and produce products or provide services at a higher efficiency, increased profitability and reduce risk to environment. CP is about minimizing the ecological impacts of our commercial and industrial activity, while maximizing the benefits gained from any raw material or resources consumed. Cleaner production aims to:
  • To minimize the creation of wastes and environmental pollution. 
  • Reduce overall costs and add market advantage. 
  • Increase resource-use efficiency and utilization. 
  • Decrease worker’s health risk, 
  • Improve public image of the industry CP approach may involve: 
  • Modifying the product to reduce its environmental impact, 
  • Substituting raw material inputs with less toxic alternatives, 
  • Modifying production processes and technologies used,
  • Good house keeping to minimize the risks of spills or leaks, and 
  • Resources recovery, recycle and reuse.
Action Plan for CP
Awareness of ecological problems is increasing. This is due to the fact that some problems are beginning to manifest themselves: global warming; shortage of waste disposal sites; increase in ground water contamination incidents; depletion of the ozone layer and increasing evidence of the adverse health effects of pollution. We must either change the way we view our place within the global ecosystem or risk a disastrous spiral from which we may never recover. Every generation has faced an uncertain future, however, none had to deal with the highest stakes of all-the survival of earth itself. Choices must be made and there are several actions you can take that can make a difference: 
  • Buy natural products like wood, cotton and wool only and purchase only containers of glass, aluminium, tin and cardboard. Avoid purchasing non recyclable plastic.
  •  Recycle everything you possibly can. When discarding anything, ask yourself where it might be utilized. Support local recycling efforts and legislation. Do not be concerned with whether you will make money on your recycling. Do it because it makes sense.
  • Get the fullest possible use of non-renewable and minimally recyclable products. Write on both sides of the paper and use that scrap wood. Simply because our society gives the illusion of free flowing resources, does not mean they should not be utilized to the maximum extent possible. Resources are too often taken for granted and misused. 
  • Be selective in purchase of wood products like paper. 
  • Be prudent about the products and packaging materials you purchase, as not all wastes can be recycled. Everyone must be accountable for their waste, so plan accordingly. Think about where it will go and how it will be disposed of when you purchase something. If there is no place to recycle it, do not buy it. 
  • Purchase products made from recycled material whenever possible. 
  • Plant native trees and see that they grow. Protest the cutting of any healthy tree in your community. Trees are often sacrificed in the name of development of new curb or underground pipe line. Even dead trees are needed by the wildlife. 
  • Minimize your use of electricity. Utilize natural light or change saving lights. 
  • Upgrade the insulation in your home. Insulate your hot water heater. 
  • Turn your thermostat down and put on a sweater. 
  • Keep your car in good condition. 
  • Take public transportation, ride your bicycle or walk instead of using your car for short distance. 
  • Obtain as much of your energy as possible from renewable sources like sun and wind. Solar water heaters are cost efficient over lifetime use. 
  • Compost household food wastes for an organic garden in your backyard. 
  • Join with the others in the cause of global ecology and supporting national environmental organizations. There is strength and power in numbers. 
It will not be enough to talk about is, but act on it. Only by action, before it is too late, can the earth be replenished and maintained as a viable support system for all inhabitants.


ENVIRONMENTAL ISSUES(very nice,it covers types of pollution and their management)

Annual Report, 2013 of Ministry of Environment, Forest and Climate Change

What is Carbon Trading ?
Carbon Trading refers to the buying and selling of the right to release carbon dioxide or greenhouse gases into the environment by various countries. The carbon trade across the world began in 1997 with the signing of Kyoto protocol in Japan by 180 countries. The Kyoto protocol called for 38 industrialised countries to reduce their greenhouse gas emission. Growing environmental pollution across the world has been a cause of concern to everyone. Rapid development and industrialisation have only added to the problem. Carbon is an element stored in fossil fuels such as coal and oil when these fuels are burnt, carbon dioxide is released. Carbon trading is like any other market trading. Carbon has been given economic value allowing people, companies or nations to trade it. If a company purchases carbon, it gets the right to burn it. Similarly, the country selling it, gives up the right to burn it. The carbon’s value is based on the ability of the carbon owning country to store it and prevent it from release into the atmosphere.

Read must
Vision IAS - Biodiversity and Environment

Vision IAS - Biodiversity Environmental Issues And Climate Change

Vision IAS - Environment : International Conventions and Related National and International Developments.

[Climate Change] Kyoto Protocol, Carbon Trading, Copenhagen Accord: Meaning, Explained
http://mrunal.org/2012/09/climate-change-kyoto-protocol-carbon-trading.html

National parks, Sanctuaries, Biosphere reserves and Botanical gardens
http://mrunal.org/2012/05/insitu-exsitu.html

Thursday, 16 April 2015

Paper 6 - General Science and Technology

Life Science
Syllabus - Introduction and applications of genetic engineering and stem cell research. Use of nano technology in the field of agriculture, animal husbandary (cloning and transgenic animals applications In Vitro Fertilisation (IVF) and genetically modified organism etc.). Biotechnology in environmental clean up process. Production of Hybrid seeds and their processing techniques, Bt cotton and Bt brinjal etc. Tissue culture and molecular markers. 

Introduction to Genetic Engineering and Its Applications( it refers to...definition of DNA, gene, genome, plasmid, genetic engineering and how it can be done)
https://www.teachengineering.org/view_lesson.php?url=collection/uoh_/lessons/uoh_genetic/uoh_genetic_lesson01.xml
Stem Cell

Useful notes on stem cells

Scientists develop cardiac cells using stem cells

How Nan Science and Nanotechnology have revolutionized Modern Technology?

Nanotechnology: It’s Approaches and Applications Mission in India

Gene Cloning: Major Steps Involved In Cloning a Gene

Difference between “Clone” and “Offspring” – Explained!

Types of Cloning: Notes on Types of Cloning

Bacteria from Antarctica aids the setting up of bio-toilets in India

Use of Biotechnology for Cleaning Up Our Environment

Bt Cotton

Bt Brinjal

GM Crops 
The Big Four: Soybean, Maize, Rapeseed and Cotton

Tissue Culture

Wednesday, 15 April 2015

Paper 6 - General Science and Technology

Life Science
Syllabus - Biotechnology: Introduction of Biotechnology, its potential to improve human life and national economy through agriculture (biofertilizers, biopesticides, biofuels, genetically modified crops), industrial development and employment generation. Areas of application -pharmaceuticals, human healthcare, food technology, energy generation etc., Efforts of government in promoting biotechnology in the country. Ethical, social, legal and IPR (intellectual property rights) issues related to biotechnological development. 

Biotechnology – An Introduction to Biotechnology
http://www.yourarticlelibrary.com/essay/biotechnology-an-introduction-to-biotechnology-essay/29356/

[Biosafety] Genetically Modified Crops, Bt-Brinjal, Cartagena & Nagoya Protocol: Meaning, Issues
http://mrunal.org/2012/08/sci-gm-crop.html

GS3 Science-Tech: Biotechnology, Robotics, Nanotech, Computer/IT awareness, Space-tech, Agro, Defense
http://mrunal.org/2014/12/mains-gs3-science-tech-biotechnology-robotics-nanotech-it-awareness.html

Biotechnology: Meaning, Technologies and Applications in India(8617 words)
http://www.yourarticlelibrary.com/biotechnology/biotechnology-meaning-technologies-and-applications-in-india-8617-words/11249/

Various Applications of Plant Biotechnology
http://www.yourarticlelibrary.com/biotechnology/various-applications-of-plant-biotechnology-biotechnology/29354/

United Nations Conference on Trade and Development
The Biotechnology Promise
http://unctad.org/en/docs/iteipc20042_en.pdf

Har Gobind Khorana: Essay on Har Gobind Khorana
http://www.yourarticlelibrary.com/essay/har-gobind-khorana-essay-on-har-gobind-khorana/28414/

Industrial Biotechnology : An Introduction to Industrial Biotechnology and it’s Applications
http://www.yourarticlelibrary.com/biotechnology/industrial-biotechnology-an-introduction-to-industrial-biotechnology-and-its-applications/29367/

Biotech could take India ahead
http://www.newindianexpress.com/education/edex/Biotech-Could-Take-India-Ahead/2015/02/23/article2678039.ece

Biocon’s breast cancer drug to hit markets next month
http://indianexpress.com/article/business/business-others/biocons-breast-cancer-drug-to-hit-markets-next-month

Defending India’s patent law
http://www.thehindu.com/opinion/op-ed/defending-indias-patent-law/article5998640.ece

Algae proposed as a viable source to produce cheaper biofuel
http://www.thehindu.com/sci-tech/science/algae-proposed-as-a-viable-source-to-produce-cheaper-biofuel/article5733023.ece

Indian biotech aiming to be $100-bn sector by 2025: Shaw
http://www.thehindu.com/business/Industry/indian-biotech-aiming-to-be-100bn-sector-by-2025-shaw/article5358221.ece

Bioechnology(Government promotion in India)
http://www.investindia.gov.in/biotechnology-sector/

Modi bets on GM crops for India's second green revolution
http://www.reuters.com/article/2015/02/22/us-india-gmo-insight-idUSKBN0LQ00Z20150222

GEAC clears field trials for GM crops
http://www.thehindu.com/news/national/geac-clears-field-trials-for-gm-crops/article6225697.ece

Ethical Issues in Genetic Engineering and Transgenics
http://www.actionbioscience.org/biotechnology/glenn.html

Convention on Biological Diversity
http://en.wikipedia.org/wiki/Convention_on_Biological_Diversity

Cartagena Protocol on Biosafety
http://en.wikipedia.org/wiki/Cartagena_Protocol_on_Biosafety

Nagoya Protocol
http://en.wikipedia.org/wiki/Nagoya_Protocol

GM CROP
Genetically-modified foods (GM foods) are been in the news lately. European environmental organizations, India and public interest groups have been actively protesting against usage of GM foods for months. 
The former environment minister of India told the apex regulator of genetically modified organisms (GEAC) that it failed to properly use available science to determine the safety to human health and environment in 2010.
There is fierce opposition from activists even to the introduction of the Biotechnology Regulatory Authority Bill (BRAI) in Parliament, meant to evolve a scientific basis for the regulatory process.

What is GM CROPS?
•These crops have been modified in the laboratory to enhance desired traits such as increased resistance to herbicides or improved nutritional content. 
The enhancement of desired traits are undertaken through breeding, but conventional plant breeding methods are  time consuming and are often not very accurate.
•Transgenic (or genetic modification) technology, which includes Bt (Bacillus thuringensis toxin) crops, combats abiotic stresses and improve nutritive quality of the grain. 
•Transgenic technology is only one component of agri-biotech, which includes non-GM options such as marker-assisted selection breeding (MAS), reverse breeding, grafting non-GM scion onto GM-root stocks etc.
•Genetic engineering can create plants with the exact desired trait very rapidly and with great accuracy. For example, plant geneticists can isolate a gene responsible for drought tolerance and insert that gene into a different plant. The new genetically-modified plant will gain drought tolerance as well.
•Not only can genes be transferred from one plant to another, but genes from non-plant organisms also can be used. The best known example of this is the use of B.t. genes in corn and other crops. B.t., or Bacillus thuringiensis.

Purpose of research on GM crops
•To overcome national issues concerning lost revenues for farmers, breeding companies and consumers, brain drain and lost technology innovations, reduced agricultural productivity and sustainability, foregone health benefits, especially reducing malnutrition.
•If rice could be genetically-engineered to contain additional vitamins and minerals, nutrient deficiencies could be alleviated. For example, blindness due to vitamin A deficiency is a common problem in third world countries

GM crop features
•GM is not a stand-alone technology. It can blend with conventional technologies, including organic farming. In fact, it is ideal to have a Bt crop as central to organic farming, since the overall objective is to decrease use of chemical pesticides.
•Thus, drought-tolerant maize and quality protein maize have been developed using Market Assistant Selective Breeding (MAS). Golden rice has been developed using the GM approach with two genes, one from daffodil and another from a soil bacterium.

GM crop promises to meet needs in many ways like
Pest resistance
Crop losses from insect pests can be staggering, resulting in devastating financial loss for farmers and starvation in developing countries.
Herbicide tolerance
Farmers often spray large quantities of different herbicides (weed-killer) to destroy weeds, a time-consuming and expensive process.
Disease resistance
Plant biologists are working to create plants with genetically- engineered resistance to these diseases.
Cold tolerance
Unexpected frost can destroy sensitive seedlings. An antifreeze gene from cold water fish has been introduced into plants such as tobacco and potato.  
Drought tolerance/salinity tolerance
Creating plants that can withstand long periods of drought or high salt content in soil and groundwater will help people to grow crops in formerly inhospitable places.
Nutrition
Malnutrition is common in third world countries where impoverished peoples rely on a single crop such as rice for the main staple of their diet. However, rice does not contain adequate amounts of all necessary nutrients to prevent malnutrition.

Reasons for embargo on GM crops
•Technical expert committee of India feels that the technology in the field of biotechnology is relatively new and there is limited information on safety, especially food safety.
•Effects of long-term and widespread consumption and commercial release of GM crops in the environment.
•No enough or extensive field trails to evaluate the health and environmental aspects of allowing GM crops.
•Concentration of intellectual property and resources for research on GM crops in the private sector was resulting in perverse and exploitative relationships of public institutions with the private sectors in developing countries and that these had not been successful in meeting the development and sustainability goals. ( this view held that the control of GM crop biotechnology by private sector was affecting the ability to deploy it towards the public good in developing countries).
•The cost of GM seeds is the fastest growing expense for U.S. farmers who are simultaneously suffering from weeds resistant to the herbicides excessively used on GM crops and pests resistant to the insecticides over-used in Bt crops. That likely would be India’s experience had it commercialized Bt brinjal which was developed with the least effective form of Bt for the target pest.

Transgenic (or genetic modification) technology in India and necessary developments and limitations
•In our country, agricultural biotechnology has been reduced to Bt (Bacillus thuringensis toxin)-crops and further restricted to Bt cotton and Bt brinjal.
•If India has become a cotton-exporting country from a cotton-importing one, Bt cotton has played an important role in this change. The sustainability of Bt cotton would require both gene pyramiding along with IPM, NPM strategies, including crop rotation.
•Livestock fed on Bt corn are the main source of meat products, imported even by Europe. One needs to worry about water availability, loss of soil fertility and hostile weather conditions. Scientists are already looking for a cold shock protein to overcome drought stress, or a nitrate reductase gene that lets the organism grow with 100 times less nitrogen than normal.

GM technology of US (vs.) NON-GM’s of European countries
•Western Europe’s maize yields match or exceed the U.S.’ yields using less pesticide. The yields in wheat and oilseed rape are increasing at an even faster rate in Western Europe than in the U.S. and Canada.
•This indicates a dangerous trend: those countries choosing to innovate in agriculture using GM are demonstrating lower productivity increases and greater dependence on chemical inputs in all crops compared to economically and environmentally comparable countries choosing to not use GM crops.
•GM products attract the strictest intellectual property (IP) rights instruments possible in agriculture (e.g., process patents).

The very existing issue draws national concern as major part of Indian population is under poverty. Now as our whole country is expecting a lot from FOOD SECURITY BILL. At this very moment if we implement total embargo and oppose BRAI in parliament, it will not solve the problem of food scarcity and poverty in our country. Sole dependency on GM crops poses a greater threat in future for children suffering from under and malnutrition.

India being a part of GM technology needs genes from plants with deep roots that can use water and nutrients very effectively. These areas of research are extremely important and must be protected from hypothetical risks. Growing GM and NON-GM crops parallelly can ease some difficulties to a particular extent.                       

Supporting communities with education on nutrition and farmers with technologies that build up their soils manage pests with little or no application of pesticide and manufactured fertilizers gives them the means and independence to grow a variety of crops and livestock to meet their dietary needs and sell their surplus in local markets. 

This investment in agriculture is not as good at making intellectual property, but better for growing food. To support India’s mainly small holder farming requires removing the penalties and incentives on the public scientist to develop primarily technologies that bring direct revenue to their institutions. Instead, invest in them with public money and measure their success by the yields of farmers, the reduction of pesticides and fertilizer they use, and the increase in their wealth and health.

India needs agriculture technology policy. Expert group need to decide year after year which crop, which trait and which strategy has to be used. Bt brinjal embargo cannot seal the fate of our country. These contentious issues can be debated only if the bill is introduced in our parliament. 

GMOs and Related issues
What are GMOs?
Genetically Modified Organisms- Refers to the organisms such as yeast, plants, animals etc whose genes have been altered.

How are GMOs made?
Aim is to change the genetic make-up. So, it can be changed by inserting new gene or modifying existing one.
Can be done by- Making the cell membrane more porous and inserting new gene into cell by electric shock, gene gun, cold temperature shock etc
Occurs in nature too.

Use of GMOs?
-Better varieties of crops (more productivity, shelf life, flood and drought resistance) = Genetically Modified Crops (GMCs)
-Ornamental organisms (GloFish was the first such organism)
-Better meat (genes can be stimulated for more muscle growth)
-Gene therapy, research etc

Why is it in news?
1.Technical Expert Committee established by Supreme court recommended a 10 yr moratorium on field trials of GMCs
2.BRAI Bill
3.Mutation breeding technology developed by BARC
4.Human cloning
5.‘Next Generation Sequencing’
6.Gene Therapy

Explanations:
1. TEC’s moratorium:
-The report criticizes the state of regulatory affairs with regard to modern biotechnology 
-Moratorium until there is more definitive information from sufficient number of studies as to the long-term safety of Bt in food crops
-no desperate shortage of food in India. It recommended that the release of GM crops for which India is a centre of origin or diversity as in Bt brinjal should not be allowed.
Why GMCs should be allowed?
1.GM crops are already widely used. Last yr, 12% of global crop area was grown with GE varieties of Soyabean, maize, cotton, rapeseed, sugarbeet
2.Over next 50 yrs, global demand for agricultural products may double. Agricultural supply needs to be doubled without straining the environment
3.Agriculture needs to be treated as a knowledge driven industry, not just a traditional vocation
4.India has become a cotton exporting country from cotton importing one because of Bt Cotton. Yields increased by 25%. Insecticide spray reduced by 50%
5.China has 6000 PhDs in agri-biotech alone. India has 8900 PhDs in all Sciences put together. No field trials->No claim substantiated. Too many hurdles for scientists: funding, activists, loss of trial crops, no publications, no products
Conclusion: GMCs should not be considered as a substitute for improved agronomy or other innovations. But a moratorium is not the answer. GMCs require sensible regulation.

Points against GMCs:
1.GMCs have both serious scientific unknowns and lack a clear social benefit, atleast for now
2.GM is a distraction from investing in real solutions by trying to overcome the environment by using genetics
3.Herbicide use is increasing in US since it adopted GM Maize, soybeans and cotton. Insecticide use is much high in US compared to France which does not use GMCs
4.Patent problems- Process patents make the crop very expensive
5.Undermines biodiversity
6.No validated surveillance to know the effect of GMCs on human health
Conclusion- GM is not a permanent solution. Use technology to better soil health, irrigation. Organic farming is a solution too.

2. BRAI BILL: Biotechnology Regulatory Authority Bill
Status: pending in Lok Sabha
Objective: to promote safe use of modern biotechnology by enhancing the effectiveness and efficiency of regulatory procedures. 
Features: 
1. The Bill establishes the Biotechnology Regulatory Authority of India [Authority= chairperson, two full time members, and two part time members]
2. Functions of the Authority: regulating the research, transport, import, containment, environmental release, manufacture and use of organisms and products of modern biotechnology.  The Authority has the power to call for information, conduct an inquiry and issue directions for the safety of products or processes of modern biotechnology.
3.Authority’s permission will be required to conduct field trials for certain organisms or products 
4. The Bill will not apply to the clinical trials of drugs, under the Drugs and Cosmetics Act, 1940, and food or food additives or any material under the Food Safety and Standards Act, 2006.  
5. State level body: A State Biotechnology Regulatory Advisory Committee will act as a nodal agency between the state government and the Authority with regard to the regulation of modern biotechnology.
6.Appellate Tribunal: A Biotechnology Regulatory Appellate Tribunal will hear appeals against the decisions, orders or directions of the Authority.  Headed by retd judge of Supreme Court or retd Chief Justice of a High Court
7.Penalties under the Bill: The Bill imposes a penalty for providing false information and conducting an unapproved field trial

3. Mutation Breeding Technology by BARC
Background: Mutation in genes occurs in nature but it is too slow and random. Desired mutation can be generated using genetic manipulation. MBT is a method for this genetic engineering.
MBT:  
MBT started in 1973 with Trombay Groundnut (TG-1) which gave 15-20% higher yield than traditional varieties
BARC is now focusing on oilseeds and pulses as India imports 40% oilseeds and 20% pulses.

4. Human Cloning and IVF (3 parent)
Already discussed by Mrunal: http://mrunal.org/2013/09/science-tech-thehindu-june-july-aug-part-1-of-3-medical-research-healthcare-disease-opv-ipv-cloning-three-person-ivf-monocrotophos-mid-day-meal-deaths-pioglitazone.html#525

5.Next Generation Sequencing
NGS is a method to read whole genomes quickly and cheaply. Mainly chromosomes are looked upon to check for abnormality, diseases such as cancer, heart disease or Alzheimer’s
Why is it in news: A baby was born in US recently after the parents screened the genomes of embryos using NGS and chose the healthiest one for implantation. (First such baby!)
Advantages of NGS:
Pre implantation diagnosis will help so many parents who can’t have a child. It will diagnose possible diseases and prevent miscarriages. [80% of IVF embryos don’t implant or miscarry]
Disadvantages of NGS:
It’ll usher an era of Designer babies (to look for specific behavioural traits, cosmetic traits). Ethical issues!
6.Gene Therapy:
Using genetic engg to cure diseases and disabilities is called Gene therapy. Human gene therapy has been ongoing since 1990, but most of that involved non-heritable genes, called somatic (non-sex cell) gene therapy.
3 parent IVF (already discussed by Mrunal) is a type of germline modification.

Why Germline gene therapy should be allowed?
1.Better lives for many who are condemned to live with genetic diseases
2.It’ll be convergence of NBIC nanotechnology, biotechnology, information technology and cognitive science- to improve human performance. Welcomed by scientists.
Why Germline gene therapy should not be allowed?
1.Problem of designer babies (as in NGS)
2.A new class of underdogs- those who cannot afford gene therapy-would be created
3.Unforeseen, deleterious consequences: Until the child grows, it’ll be difficult to know the exact results.


Intellectual Property Rights(IP) – Are the really Intellectual ??

Prologue
1) Introduction
2) Patent
3) Bio-Piracy
4) Breast Cancer (Mastec-tomy)/ Case of Hollywood Actress Angelina Jolie
5) Myrid Genetics
6) Case Myriad Genetics vs Association of Molecular Pathology
7) Novartis  vs Supreme Court of India (Land Mark Judgement by Supreme Court)
8) Bayer Cancer Drug
9) What is TRIPS

Introduction  

•Intellectual property rights are the rights given to persons over the creations of their minds. They usually give the creator an exclusive right over the use of his/her creation for a certain period of time.
•IP are divided into 2 main areas 

a)Industrial property, which includes inventions (patents), trademarks, industrial designs, and geographic indications of source;
b)and Copyright, which includes literary and artistic works such as novels, poems and plays, films, musical works, artistic works such as drawings, paintings, photographs and sculptures, and architectural designs.  Rights related to copyright include those of performing artists in their performances, producers of phonograms in their recordings, and those of broadcasters in their radio and television programs

Patent
•It is an exclusive right granted for an invention, which is a product or a process that provides, in general a new way of doing something that offers a new technical solution to a problem.
•A patent provides protection for the invention to the owner of a patent which is granted for a limited of 20 years. Patent protection means that invention cannot be commercially, made, used, distributed or sold with the patent owner’s concern.


Gene Patent

•It is a patent on a specific isolated gene sequence, its chemical composition, the process for obtaining or using it or combination of such claims.
Geographical Indications
•A geographical indication is a sign used on goods that have a specific geographical origin and possess qualities, reputation or characteristics that are essentially attributable to that place of origin.
•Most commonly, a geographical indication includes the name of the place of origin of the goods. Agricultural products typically have qualities that derive from their place of production and are influenced by specific local factors, such as climate and soil. Whether a sign is recognized as a geographical indication is a matter of national law. 
•An appellation of origin is a special kind of geographical indication. It generally consists of a geographical name or a traditional designation used on products which have a specific quality or characteristics that are essentially due to the geographical environment in which they are produced.  The concept of a geographical indication encompasses appellations of origin.
E.g  Darjeeling Tea, Kullu Shawl of Himachal and Mysore Sandal Soap of Karnataka

Bio-Piracy
•Bio-Piracy is the unauthorized use of the genetic resources & the knowledge associated with genetic resources held by the communities living  from Bio-diversity rich countries, which may be infringed upon illegally by industrial enterprises
•Bio-piracy is a part of a larger problem whereby developing countries rich in biodiversity, are exploited by transnational corporations and industries that make use of these resources.
•Bio-piracy, refers to the appropriation, generally by means of patents of legal rights over biological materials by international companies to develop food or medicines, without recompensing the countries from which they are taken


Breast Cancer

•Breast cancer is a type of cancer originating from breast tissue, most commonly from the inner lining of milk ducts or the lobules that supply the ducts with milk.
•Breast cancer occurs in humans (men also) and other mammals. A distinct sequence of nucleotide forming part of a chromosome is known as gene. Protein controls structure & function of all the cells that make up the body.
•The complete DNA instruction book or GNOME for humans contain 3 billion bases & about 20,000 genes on 23 pair of chromosomes. And abnormalities in the DNA or abnormal changes may provide wrong set of instructions leading to faulty cell growth and function.
•Most inherited( mostly from parents) cases of Breast cancer are associated with 2 abnormal genes BRC -A1 & BRC-A2 (BR=BREAST & C=CANCER)
•Function of BRC-A genes is to repair cell damage & keep the breast cells growing normally, but when these genes contain abnormality or mutation(The changing of the structure of a gene, resulting in a variant form that may be transmitted to subsequent generations) these genes do not function normally & breast cancer risk increases
Mastectomy ( Greek word: breast + removal )
•A mastectomy is surgery to remove a breast. It is performed either to treat or to prevent breast cancer. Only high-risk patients have surgery to prevent cancer. 
•There is a relationship between diet and breast cancer, including an increased risk with a high fat diet, alcohol intake, and obesity. Other risk factors include radiation and shift-work
There are four main types: (Not important)
•Total mastectomy - removal of breast tissue and nipple
•Modified radical mastectomy - removal of the breast, most of the lymph nodes under the arm and often the lining over the chest muscles
•Lumpectomy - surgery to remove the tumor and a small amount of normal tissue around it
•Radical mastectomy - the removal of the breast, lymph nodes and chest muscles. This is no longer common

Case of  Angelina Jolie

•Angelina Jolie drew headlines with her announcement that she has undergone a preventative double mastectomy. A blood test revealed that she carries a damaged BRCA1 gene -- a defect that greatly increases the odds of a woman getting breast cancer. 
•She had  an 87 percent chance of developing the disease, she decided to undergo a prophylactic double mastectomy, an operation that reduced her risk to 5 percent.
•The first issue is the test. The BRCA1 and BRCA2 tests, which may have saved Jolie's life, cost $3,000 to administer (Please note this – Its very costly not affordable by everyone.)

Myriad Genetics
•Myriad genetics is a molecular diagnostic company based in salt lake city in U.S.A
•Myriad was having exclusive licensing right in the U.S for breast cancer analysis & testing- this is a molecular diagnostic product used for analysis of BRC-A1 & BRC-A2 to evaluate a women’s risk of developing hereditary breast cancer. It helps women to determine if they have BRC-A1 & BRC-A2 gene mutations which will be helpful in determining the preventive & guiding therapy.
•Myriad genetics for its breast cancer risk assessment involving the genes BRC-A1 & BRC-A2 was charging significantly about $3000, those arguing against the patenting of the genes claimed that the high cost of the test was due to the monopoly over it by Myriad genetics, so a case was filed against Myriad genetics in the U.S  court

Case Myriad Genetics vs Association of Molecular Pathology

•The Association for Molecular Pathology along with several other medical associations, doctors and patients sued the United States Patent and Trademark Office (USPTO) and Myriad Genetics to challenge several patents related to human genetics. The patents cover the BRCA1 and BRCA2 genes and certain mutations that indicate a high risk of developing breast cancer.
•The suit also challenged several method patents covering diagnostic screening for the genes. They also argued that the patents limit scientific progress. Limits patents to “any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof.
•By patenting the genes, Myriad had exclusive control over diagnostic testing and further scientific research for the BRCA genes. Myriad argued that once a gene is isolated, and therefore distinguishable from other genes, it could be patented.
•Holding: A naturally occurring DNA segment is a product of nature and not patent eligible merely because it has been isolated, but synthetic complementary DNA ("cDNA") is patent eligible because it is not naturally occurring.
•Judgment: Affirmed in part and reversed in part., 9-0, in an opinion by Justice Thomas on June 13, 2013. Justice Scalia filed an opinion concurring in part and concurring in the judgment.
•Because of these ruling patients will have greater access to genetic testing & scientists can engage in research on these genes without the fear of being sued.

Novartis  vs Supreme Court of India (Land Mark Judgement by Supreme Court)

•Novartis International AG is a Swiss multinational pharmaceutical company based in Basel, Switzerland, ranking number two in sales (46.806 billion US$) among the world-wide industry in 2010.
•It had developed a ground breaking super expensive cancer drug called Gleevac( Novartis Had gained patent protection for this drug in some 40-odd countries) for which it wanted patent rights in India(patent rights are different for different countries)
•Case was filed and Supreme court of India rejected the application which was a landmark judgment
Reasons for Rejection
•Novartis failed to prove the drug was “patentable”, the drug under review did not demonstrate any “significant of efficacy”(capability to produce an effect) over available generics & its active ingredient was already known
•This is a pretty common method by Pharmaceutical companies to evergreen patent protection by making minor modifications to drugs approaching Patent expiry ( 20 years …. Hope u remember or getting bored??)
•And in this way for many American Pharmaceutical companies it is easy to make market in India (India is huge market. An average man spends around 70% of his income on medicines and health problems)
•Existence of Robust property rights are a key bench mark for development as they reflect institutional strength (via a judiciary)
•India has over 28 lakh cancer patients. Supreme Court judgment can make a way for cancer patients getting cheaper drugs as a 1-month dose of Gleevec costs around Rs 1.2 Lakh and the same generic drugs manufactured by Indian company for the same period is priced at Rs 8000.

Bayer Cancer Drug

•An Indian patent appeals Board upheld  a decision to allow a domestic company to sell a generic version of BAYER AG(German chemical and pharmaceutical company) cancer drug NEXAVAR, in blow for global drug makers efforts to hold on to monopolies on high price medicine.
•This ruling was again a landmark as it paves the way for the issue of more so called compulsory licenses as governments particularly in emerging markets such as China & Thailand, battle to bring down health care costs & provide access to affordable drugs to treat diseases such as cancer, HIV-AIDS.
•The Indian Patent Office(IPO) is administered by the Office of the Controller General of Patents, Designs & Trade Marks (CGPDTM). This is a subordinate office of the Indian Government and administers the Indian law of Patents, Designs and Trade Marks
•IPO allowed NATCO Premium Pharma (Indian Company) to sell the generic Nexavar at Rs 8800 or $160 for a month’s dose but for which Bayer was charging Rs 2,80000(only .. lolz)
•Bayer challenged it & the board did order NATCO Pharma to pay a royalty of 7% on sales of generic Nexaver to Bayer
India’s vision = Kidney & Liver cancer drug should be available at an affordable price to everybody

What is Trips?

•The Agreement on Trade Related Intellectual Property Rights (TRIPS) was negotiated with other international trade agreements during the Uruguay Round trade negotiations of the GATT (General Agreement on Tariffs and Trade) from 1986 to 1994.
•As one of the World Trade Organization (WTO) agreements, it is totally binding for all WTO Member States (whether a previous GATT Member or a new WTO one)
•Taking into account the transitional periods allowed to developing and least-developed countries by the TRIPS Agreement.
•The TRIPS Agreement sets minimum standards in the field of intellectual property (IP) protection (such as copyrights, patents, and trademarks) that all WTO Member countries have to respect.
•To achieve this goal, WTO Members have to modify their intellectual property laws to make them consistent with the new WTO standards.

•For instance, the TRIPS Agreement states that all patents shall be available for at least 20 years from the filing date, whereas before TRIPS the patent term varied greatly among countries (7, 10, 17 or 20 years). All WTO Members have to incorporate this 20-year patent term in their own patent law.

Friday, 27 March 2015

Paper 6 - General Science and Technology

Life Science

Introduction to basic functional aspects of mammalian systems- digestive, circulatory, respiratory, nervous, excretory, endocrine and reproductive

1. The Mammalian Digestive System

The mammalian digestive system consists of the alimentary canal ( complete digestive tract) and various accessory glands that secret digestive juices into the canal through the ducts. The food is moved along the tract by the contraction of smooth muscles in the walls of the canal.  These rhythmic contraction waves are called peristalsis.  The regulation of passage of material from one chamber to another within the canal is controlled by ring-like valves called sphincters.

The accessory glands of the mammalian digestive tract are three pairs of salivary glands, the pancreas, the liver, and its storage organ the gall bladder.

Now lets  follow a meal through the human digestive canal. 

The Oral Cavity – Mouth
Physical and chemical digestion of food begin in the mouth.  During chewing the food is made easier to swallow and the food’s surface area is increased.   The presence of food in the mouth triggers a nervous reflect that causes the salivary glands to secret saliva into the mouth. Often saliva is secreted due to a smell or sight.  In humans , almost a liter of saliva is secreted into the mouth daily. That may sound like a lot, but for horses it is gallons! Human saliva contains mucin which is a slippery glycol-protein which protects the mouth from abrasion and lubricated  the food for swallowing. Saliva contains buffers that help prevent tooth decay by neutralizing acids in the mouth.  There are also antibacterial agents in the saliva. The digestion of carbohydrates begins in the mouth.  Saliva contains salivary amylase, a digestive enzyme that hydrolyses starch (a glucose polymer from plants and glycogen (a glucose polymer from animals).  This enzyme breaks down the carbohydrates into smaller polysaccharides and the disaccharide maltose. The tongue located in the oral cavity helps to manipulate the food during chewing and shapes the food into a ball called the bolus which it pushes to the back of the mouth and into the pharynx.

The Pharynx
Out throat is the pharynx which leads to both the esophagus and the windpipe (trachea).
When a human swallows the to of the windpipe moves up so that its opening , the glottis, is blocked by a flap of cartilage called the epiglottis. This helps to ensure that the bolus enters the esophagus.

The Esophagus
The esophagus channels food from the pharynx to the stomach. The muscles in the walls move the food. The first part of swallowing is a voluntary act but then the involuntary waves of contraction of the smooth muscles take over. Salivary amylase continues to hydrolyze starch as the bolus passes through the esophagus.


The Stomach
The stomach is located on the left side of the abdomen , just below the diaphragm. Since its walls are elastic and it has accordion-like folds, the stomach can hold up to 2 liters of food and water. The walls of the stomach secret gastric juices, a digestive fluid that mixes with the food. Since this fluid has a high percentage of HCl , its pH is about 2 which is acidic enough to dissolve iron nails. The functions of this acid include : 1. disrupt the extra-cellular matrix that binds cells together 2. kill most bacteria in the food.
Also present in this gastric juice is pepsin, an enzyme that begins the hydrolysis of proteins by breaking peptide bonds.  Cells of the stomach wall are protected from pepsin by a coating of mucus.  The epithelial cells which generate this mucus are eroded by the acid  and therefore the stomach lining must be replaced by mitosis every three days.

Much of the time the stomach is closed off at both ends. The opening from the esophagus to the stomach is called the cardiac orifice. This opening will open when a bolus is ready to pass.  Occasionally there will be backflow of acid chime from the stomach  into the lower ed of the esophagus, causing heartburn.  If heartburn persists, An ulcer could develop in the esophagus.  The opening from the stomach to the small intestine is the pyloric sphincter. This opening regulates the passage of chime into the small intestine. This happens a squirt at a time, taking about 2-6 hours to empty the stomach after a meal.

Small  Intestine
The small intestine is the major organ of digestion and absorption. The small intestine is the longest section of the digestive tract at more than 6 meters in length.  It is referred to as the small intestine because its diameter is smaller than the large intestine. Most digestion and absorption happens in this organ. The pancreas, liver and gall bladder  participate in digestion.

The first part of the small intestine is called the duodenum ( about 25 cm in length). This is where the chime from the stomach mixes with digestive juices from the pancreas, liver gall bladder and gland cells from the intestinal wall. The pancreas produces bicarbonate which helps to offset the acidity of the stomach. The liver produces bile which is stored in the gall bladder. Bile does not contain digestive enzymes. It contains bile salts which act as detergents and aid in the digestion and absorption of fats. Bile also carries wastes from the liver (where old red blood cells are destroyed).

Carbohydrate digestion
Pancreatic amylases hydrolyze starch, glycogen, and smaller polysaccharides into disaccharides including  maltose. The enzyme maltase completes the digestion of maltose by splitting it into two molecules of glucose. Sucrase hydrolyzes sucrose ( table sugar). Lactase digest lactose ( sugar found in milk).  As people get older, they have less lactase in their system. These disaccharidases are in the membranes of the intestinal epithelial where the final monomers are absorbed by the blood.

Protein digestion
Enzymes in the duodenum break the polypeptide chains down into amino acids. These enzymes are supplies by the pancreas.

Nucleic acid digestion
Enzymes called nucleases hydrolyze DNA and RNA in food into their nucleic acids. Other enzymes break the nucleotides down.

Fat digestion
Nearly all the fat in a meal reaches the small intestine completely undigested. Fat molecules are insoluble in water. Bile salts coat the tiny fat droplets to keep them from coalescing in a process called emulsification.  Since the droplets are small, a large surface area is exposed to lipase which is an enzyme which hydrolyzes fat.  Most of this digestion happens in the duodenum. The remaining regions of the small intestine, jejunum and ileum, function mainly in the absorption of nutrients and water.

Absorption of nutrients
Most of the absorption of nutrients takes place in the small intestine while there is some absorption in the stomach and small intestine. The lining of the small intestine has a surface area about the size of a tennis court. Large circular folds in the lining have villi and each of the cells of the villi have microvilli. These villi absorb nutrients which are then transported across the capillary membranes. 

Large Intestine
The large intestine or colon is connected to the small intestine at a T-shaped junction where a sphincter regulates the movement of materials. One arm of the T structure is a sac called the cecum which has a fingerlike extension called the appendix. The main part of the colon is an upside down U about 1.5 meters in length. Connected to the cecum is the right or ascending colon which is connected to the transverse colon which is connected to the descending colon which is connected to the sigmoid colon which is connected to the rectum.
The main function of the colon is to reabsorb water although most re-absorption of water happens in the small intestine with the absorption of nutrients.  The small and large intestines absorb about 90% of the water that enters the digestive tract. The wastes of the digestive tract, feces, become more solid as they move along the colon.

Many harmless bacteria live in the colon. E. coli is in the colon. Intestinal bacteria live on organic bacteria that would otherwise be included in feces. By-products of colon bacteria metabolism include gases (like methane and hydrogen sulfide) and some vitamins. Bacteria in the colon generate Vitamin K which is used in blood clotting. The terminal portion of  the colon is called the rectum which is where feces are stored until they can be eliminated. Between the rectum and the anus are two sphincters, one involuntary and one voluntary. Once or more a day, strong contractions of the colon create an urge to deficate.

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2. Animal Respiratory System
Every cell in an animal requires oxygen to perform cellular respiration which gives off carbon dioxide and water as waste products. Respiration is the process by which animals exchange these gases with their environment. Animals have specialized systems of structures that help them to do this successfully and efficiently. Even a fish will drown if it cannot successfully breathe underwater.

Gas Exchange
The actual exchanging of the gases is dependent upon important structures such as lungs or gills, and the principle of diffusion. Diffusion says that the molecules or particles will move from an area where they are very concentrated into an area where they are less concentrated.

Mammals Respiratory System
The chief organ in mammalian respiration is the lungs. The lungs are actively ventilated via a suction-pump mechanism of inhalation and exhalation. Breathing is dependent upon the rib muscles and the diaphragm, which is a structure located just beneath the lungs like a dome-shaped floor (or a dome-shaped roof for the intestinal cavity.

Inhalation happens when the rib cage opens up and the diaphragm flattens and moves downward. The lungs can then expand into the larger space that causes the air pressure inside them to decrease, and the drop in air pressure inside the lung makes the outside air rush inside. 

Exhalation is the opposite process. The diaphragm and the rib muscles relax to their neutral state that causes the lungs to contract. The squashing of the lungs increases their air pressure and forces the air to flow out.
A diagram of ventilation in most mammals. The left image shows inhalation with a flattened diaphragm. The right side shows the dome shaped diaphragm forcing the air out during exhalation.

In most mammals, the first place that air enters upon inhalation is the nose. It gets warmed, moistened, and filtered by cilia and mucus membranes which can trap dust and pathogens. Air then reaches the epiglottis, which is the tiny leaf shaped flap at the back of the throat. The epiglottis regulates air going into the windpipe and closes upon swallowing to prevent food from being inhaled. It is the gatekeeper to the lungs. If the epiglottis is the gatekeeper, who's the key master?
The trachea is a long structure of soft tissue surrounded by c-shaped rings of cartilage. In humans the trachea splits into two bronchi branches that lead to each lung. Each bronchi divides into increasingly smaller branches, until they form a massive tree of tubes. The smallest branches are called the bronchioles, and each bronchiole ends with a tiny air sac (no larger than a grain of sand) called an alveolus.
The tiny alveoli (alveoli is the plural of alveolus) are crucial because they increase the surface area that can be used for gas exchange. If the lungs were just empty sacs the only area available for gas exchange would be the walls of the lungs, which in humans is approximately 0.01 meters squared. In contrast, the alveoli structures provide 75 square meters of surface area where oxygen absorption can take place. That is the size of half a volleyball court.
Diagram of an alveolus near a capillary and the gas exchange process in the lungs

As discussed above, gas exchange takes place in the capillaries, so the alveoli are closely aligned with the network of capillaries. This brings the blood carrying waste products into close enough proximity with fresh air for diffusion to take place. The waste is removed and the oxygen is taken up by the blood.

The blood is able to carry the fresh oxygen in red blood cells because of the hemoglobin protein, which can attach oxygen molecules. Think of hemoglobin like a bus that carries oxygen passengers. Each hemoglobin protein can carry four passengers of oxygen at one time. 

When red blood cells are oxygen rich they are bright red, and when they are deoxygenated they are a deep purple. When the blood reaches the systemic capillaries near the cells, the carbon dioxide and oxygen diffuse in opposite directions. 

After circulating through the heart, the blood arrives at the capillaries near the lungs. Water vapor and carbon dioxide are exhaled, and the process begins again with inhalation.

Just as the heart beats on its own, following sinoatrial node signals, breathing is done without conscious effort. There are sections of the brain, called the medulla and pons, that regulate respiration. They decide how fast respiration needs to take place by monitoring the level of carbon dioxide in the blood. In times of excitement or during exercise, the cells require more oxygen than normal. Respiration speeds up. Additionally, the heartbeat increases because the circulatory system is required for the respiration system to function.

Tidal volume is the amount of air breathed in or out during a respiratory cycle. The tidal volume and respiratory frequency vary amongst species and can also be affected by age, pregnancy, exercise, excitement, temperature, and body size. Horses have an average respiration of 12 times per minute, but pigs breathe an average of 40 times per minute.

Horses are obligate nasal breathers, which means that they must breathe through their noses. Humans and many other mammals can breathe through either their mouths or their nasal passages. A horse cannot breathe through its mouth. It is thought that this modification allows horses to graze with their heads down while separate nasal passages breath in air and sniff for potential predators.

Marine mammals breathe oxygen with lungs just like their terrestrial brethren, but with a few differences. First of all, to prevent water from getting into their airway they have adapted muscles or cartilaginous flaps to seal their tracheas when under the water. Additionally, they exchange up to 90% of their gases in a single breath, which helps them gather as much oxygen as possible. A sperm whale can last for 138 minutes on a single breath.

Lastly, it can be dangerous for diving mammals to have air in their lungs when they dive to great depths. For this reason, many marine mammals will prepare for a deep dive by taking a breath, exchanging gases in the blood, and exhaling to empty their lungs.


Diagram of structures of the lungs

Reptiles and Amphibians
Reptiles and amphibians both have lungs and exchange gases in the capillaries like mammals, but there are some differences in how they ventilate their respiratory systems. Reptiles do not typically breathe the same way as mammals since many reptiles lack a diaphragm. Without it they rely on muscles used in locomotion to ventilate their lungs.

Amphibians are capable of buccal pumping to push air into the lungs. This begins by muscles pulling air through the mouth or nose into a buccal cavity. Throat muscles then pump and move the floor of the mouth up in a way that Is visible from the outside. This forces air out of the mouth and into the lungs. Have you seen at frog's throat that is constantly moving.

Apart from their capillaries, amphibians can also perform gas exchange directly through their highly vascularized skin. This means that their skin has lots of blood vessels going through it. Since the blood vessels are close to their permeable skin surface, diffusion can take place right through the skin. In fact, some salamanders have no lungs at all, and they get all of their oxygen through their skin. The take home message is never get in a breath holding contest with a salamander. We wouldn't recommend a staring contest, either.

Birds
The respiratory system of birds is similar to that of mammals. Air is pulled in using a suction-type pull. Gases are exchanged in the capillaries. The major difference is the route of airflow through the bird. Birds have air sacs that collect air. They then force the air through their lungs like bellows stoking a fire. 

When a bird inhales, air is brought into the posterior air sacs, which expand. Upon exhalation, the air is forced from the posterior air sacs into the lungs. This is where gas exchange takes place. A second inhalation will move the air from the lungs to the anterior air sac. A second exhalation will push the air out of the body. 

This progression of air through the bird means that the lungs are compressed during inhalation and expand during exhalation. It also takes two full inhalations and exhalations to move one gulp of air through the bird. That's a lot of gulps.
Aquatic Respiration
In fish, respiration takes place in their gills. Gills can collect dissolved oxygen from the water and release carbon dioxide. Gills are much more complex than just a slit in the cheek of a fish. 

Gills are comprised of gill arches with hundreds of gill filaments extending from them. Each filament is lined with rows of lamellae, and the gas exchange takes place as water flows through them. The frills and flaps increase the surface area to allow more gas exchange to take place, just as the alveoli do in the lungs.

Fish utilize a countercurrent exchange pathway (except for cartilaginous fish), which means that their arteries are arranged so that blood flows in the opposite direction of water movement against the gills. By having their respiration pathway in this orientation, maximum gas exchange can take place. 

If the blood and the water were moving in the same direction, the blood would always be next to the same bit of water which would soon be depleted of oxygen. By setting up a countercurrent pathway, the blood is always passing water that still has oxygen. This allows the blood to gather as much oxygen as it can hold.

Since water must be flowing over the gills to provide a continual source of oxygen, fish have developed several ways to keep them ventilated. Some fish swim with their mouths open almost all of the time. Other fish have a special flap called an operculum, which is used to force water across the gills. 

The exception to all fish having gills is the lungfish, which has working lungs. It can survive when its water habitat dries up from seasonal drought. Aptly named fish. Similarly, there are also certain land crabs that use gills to breathe outside of the water.

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3.Human Circulatory system
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4.Human Excretory system
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5.Human Nervous system
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6.Human Endocrine system
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7.Human Reproductive system
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