science gcse core, additional and triple science powerpoints

1. P2 Radiation and life Route map Over the next 12 lessons you will study : Friday 21 October 2011 P2.1 Sunlight, the atmosphere & life P2.2 Ozone protection P2.3 Radiation models P2.4 Electromagnetic radiation End of module test P2.5 Using radiation P2.6 Mobile phones and Health P2.7 Health Studies P2.8 X-ray safety P2.9 Global warming P2.10 The carbon cycle P2.11 Changing climates? P2.12 Time for action?

3. P2.7 Health studies Extension questions: 1: Why do scientists conduct research on the safety of new devices like mobile phones or the risk of a lifestyle factor like drinking or smoking ? 2: Why do sample sizes have to be large ? 3: Why do the people chosen have to be a) similar age b) similar ethnicity and c) have similar medical histories ? 4: Would you trust finding paid and reached by scientists employed by a mobile phone company saying that mobiles are safe Know this: a: Know how studies are carried out to provide data that is reliable, repeated and trusted by other scientists. b: know that large samples of people of similar ages are researched. Friday 21 October 2011 Introduction: Scientists will look for any harmful effects for example the development of brain tumours from using mobile phones by comparing samples of mobile phone users to non-mobile phone users. The people chosen for both groups, should be of similar age and matched for as many other factors as possible. Sample should be as large as possible with people being selected randomly to avid bias. Funding for the study should be independent of interested parties like the government or mobile phone companies. Above the data reported should be reviewed by other scientists and be repeatable.

4. P2.7 a Look at the photograph and information and answer all the questions: What to check Health surveys and even clinical trials are scientific and medical research studies designed to find better ways to treat or prevent diseases. The survey or trial itself must study a large enough sample to be meaningful and ensure that the findings can be repeated by other scientists. A survey or trail must also be free of any interested parties. Why are people and governments interested in the risk of using a mobile phone ? If mobile phones are proved to increase your risk of developing a brain tumour do you think they should still be sold ? Many studies have show a ‘cast iron’ link between smoking and lung cancer. Why do you think the government still allows their sale in shops ? Sample size Who’s in the sample group Are the outcomes different Who conducted the survey Is the sample size big enough to represent the population you are trying to study ? People in both sample should be matched for age, sex, lifestyle. When you compare the findings for the two groups are the differences significant ? Why to check Was the survey independent and free from pressure from governments or companies ? Key concepts

5. P2.7 b Look at the photograph and information and answer all the questions: The report opposite suggests that the microwaves used by mobile phones after just 2 minutes use could produce changes in the brain that could put the mobile phone user at higher risk of developing Alzheimer's an Parkinson’s disease. One expert yesterday called on children under 12 not to use mobiles except in an emergency and said “This is a warning sign. It is very worrying. We should be taking precautions.” The article opposite left report no original data like who was studied and how large the study group was. Is this a problem when trying to assessed the reports findings Later the Swedish research told press that these findings were based on a study group of less than 100 people. Is this a large enough study ? Why would knowing how much time each individuals spent using mobiles also be useful ? Key concepts

6. P2.7 Plenary Lesson summary: Decide whether the following statements are true or false : False True False True False True safety samples research numbers Over 50 million people in the UK use mobile phones. Government officers consider carefully before making public statements and giving advice on mobile phone safety. They need strong evidence that mobile phones are harmful before they can make any statements. This will be difficult as the effects of mobile phone usage will only be seen over time How Science Works: Friday 21 October 2011 Research into how X-rays have been used to image the human skeletal system and how using the principals, of ALARA minimises human exposure to ionising radiation when using X rays. Preparing for the next lesson: 3: People chosen to sample have to be similar ages ? 2: The effects of mobile phones on health can be seen instantly ? 1: Research has to be done on a small sample of people ? Scientists conduct _________ on mobile phone ________ by comparing _______of mobile phone users to non- mobile phone users. The people chosen are of similar age and there are similar _______ of people in both groups.

8. P2.8 X-ray safety Extension questions: 1: When were X-rays discovered and what can X-rays be used for ? 2: Why are X-rays dangerous and how can we people who work with this form of ionising radiation protect themselves ? 3: Why are X-rays not used to image the developing embryo of foetus when a female is pregnant ? 4: Would you expect cancer rates to be higher in radiographer who use X rays every day at work in hospitals and why do radiographers leave the room when then take an X-ray ? Know this: a: Know that X-rays are a useful medical tool when imaging the human skeletal system. b: Know that X-rays are a form of ionizing radiation and their use is governed by the principals of ALARA. Friday 21 October 2011 Introduction: X-rays were discovered in the 1890’s. Their use in hospitals and by doctors has helped save many thousands of lives. X rays are a form of ionizing radiation which can ionize molecules in your body and cause cancer. In using X rays the benefits must be balanced against risks. ALARA Using the principal of ALARA help make the patients exposure a s l ow a s r easonably a chievable make sure the benefit remain high and the risks remain low

9. P2.8 a Look at the photograph and information and answer all the questions: X-rays are a form of electromagnetic radiation, just like visible light. X-ray machines sends are individual x-ray photons. These pass through the body. A computer or special film is used to record the images that are created. Structures that are dense (such as bone) will block most of the x-ray particles, and will appear white. Why do radiographers, people who use x ray machines protect themselves from regular exposure to x rays ? Name one other use for X-rays other than imaging broken bones ? Explain why X-ray photography produces images of the bones in our body but not the flesh ? Key concepts

10. Look at the photograph and information and answer all the questions: The ALARA principle is used when using X-rays. It ensures the patient’s safety by making the exposure: a s l ow a s r easonably a chievable. The procedure is as follows: *Time: Keep the exposure time short *Distance: Keep a large distance *Shielding: Use lead to cover sensitive areas Where is the ALARA principle used and why is following the ALARA principals important in the work place ? Look at both pictures, one shows what a X ray suite use to look like, the other is a modern facility. How have they changed ? What is the procedure for the ALARA principle? P2.8 b Key concepts

11. P2.8 Plenary Lesson summary: Decide whether the following statements are true or false : False True False True False True ionizing medical discovered body Research shows that just one exposure form X-rays to a unborn foetus in the womb can double the change of that child, when born form dying from cancer. This is why X-rays are never used on pregnant females because of the high risk to the unborn foetus. Ultrasound is used to image the developing foetus. Ultrasound is a safe alterative to using X-rays How Science Works: Friday 21 October 2011 Research into global warming and the impact of rising carbon dioxide levels in the planet’s atmosphere. Preparing for the next lesson: 3: Lead can absorb X-rays ? 2: The ALARA principle is used when working with x-rays ? 1: X-rays are non-ionizing ? X-rays were ________ in the 1890’s. They soon caught on as a useful ________ tool, and they have saved many thousands of lives. But they are a form of _________ radiation which can ionize molecules in your ______ and cause cancer.

13. P2.9 Global warming Extension questions: 1: Name two so called ‘green house gases ? 2: The link between rising carbon dioxide levels and increasing global temperatures, is that sufficient to support the conclusion that global warming is caused by rising carbon dioxide levels 3: Why is atmospheric carbon dioxide levels rising ? 4: How can reduce our so called ‘carbon footprint’ ? 5: Name two major sources of carbon dioxide emissions ? Know this: a: Know the cause of global warming is linked to rising carbon dioxide levels in the planets atmosphere b: Know that the carbon dioxide molecule traps infra red heat energy form the sun’s rays. Friday 21 October 2011 Introduction: Scientists think the rise in global temperatures or ‘global warming’ is due rising levels of carbon dioxide and methane in the atmosphere. This is due to evidence that temperature and carbon dioxide levels have been increasing together over the last 150 years and the carbon dioxide molecules traps infra red heat energy form the sun’s rays. The last decade also witnessed the highest average global temperatures recorded possibly over the last two thousand years

14. P2.9 a Look at the photograph and information and answer all the questions: Scientists have many theories as to what may happen over the next century because of rising CO 2 levels in the atmosphere, as a result of combusting fossil fossils. There is now agreement amongst scientists that atmospheric carbon dioxide levels need to be controlled. Many countries have signed ‘ The Kyoto Agreement ’ which aims to reduce carbon emissions. This will perhaps slow global warming. Only one country, America has not signed up, she is the biggest carbon polluter. Explain how out atmosphere acts to insulate and keep Earth warm ? As we add more and more carbon dioxide into the atmosphere this warming effect is increases...what do we call this effect ? The power station pictured opposite left is call Drax Power Station. It is run off coal and produces about 20% of all the CO 2 in the UK...what other methods could we use to generate electricity ? Key concepts

15. P2.9 b Look at the photograph and information and answer all the questions: When hydrocarbons like methane are burnt, carbon dioxide is produced as a by product. We are adding about 3 billion tonnes of CO 2 every year to our atmosphere. This gas traps the sun's heat and has led to global warming. Coal-burning power stations and the millions of cars, lorries and planes are the largest source of carbon dioxide pollution -- they produce about 2.5 billion tonnes per year. Name three effects of global warming, for example the polar ice caps melting ? How could we reduce our carbon footprint…meaning the amount of carbon dioxide we release into the atmosphere every year ? Look at the graph left…do you think that rising amounts of CO 2 in the atmosphere is linked to increasing average global temperatures over the last 150 years ? O 2 CH 4 H 2 O CO 2 Key Substrates Products CH 4 + 2O 2 CO 2 + 2H 2 O Key concepts

16. P2.9 c Look at the photograph and information and answer all the questions: Emissions from car exhausts contain toxic gases. These gases are breathed in and transported to all the body's major organs. These pollutants include, carbon monoxide, carbon dioxide, nitrogen monoxide, nitrogen dioxide, dinitrogen oxide, sulphur dioxide, low level ozone, and particulates. The most obvious health impact of car emissions is on the respiratory system. Both nitrogen monoxide (NO) and nitrogen dioxide (NO 2 ) are toxic even at low levels causing lung damage and higher blood pressure...explain what effects these gases may have on a) an asthma sufferer and b) some with cardiovascular problems ? Cars, since 1998 have been sold with catalytic converters which reduce the amount of pollutants. Why is this a good for air quality ? What effect will sulphur dioxide (SO 2 ) have on the environment ? Ozone (O 3 ) low level Sulphur dioxide (SO 2 ) Nitrogen monoxide (NO) Nitrogen dioxide (NO 2 ) Dinitrogen oxide (N 2 O) dioxide (CO 2 ) Carbon monoxide (CO) Carbon Particulates Key concepts

17. P2.9 Plenary Lesson summary: Decide whether the following statements are true or false : False True False True False True warming methane global increasing Although scientists have recorded daily temperatures over the last 150 years which show an increase of about 0.5 o C, the real evidence of climate change comes from growth rings in trees and air trapped in ice found in the polar regions. Tree ring growth can give us about a thousand years worth of data but using ice cores can give us nearly 600,000 years worth of data How Science Works: Friday 21 October 2011 Research into the carbon cycle and how man’s activities is pumping an additional 3 billion tones of carbon dioxide into pour atmosphere every year. Preparing for the next lesson: 3: The greenhouse effect can cause climate change ? 2: Methane is a green house gas ? 1: Increasing atmospheric carbon dioxide does not lead to global warming? Scientists think the rise in _______ temperature or global ________ is due the rising levels of carbon dioxide and_________ in the atmosphere. This is due to evidence that temperature and carbon dioxide levels have been ________ together.

19. P2.10 The carbon cycle Extension questions: 1: Name three stores of carbon or carbon dioxide ? 2: In the 1800s the ppm of CO 2 was around 277, now it is risen to 370 ppm. Why has this rise in CO 2 levels happened ? 3: How are fossil fuels made and Name three types of fuel ? 4: What happens when we burn fossil fuels in power station or in vehicles like cars and lorries ? 5: How can we reduce the amount of CO 2 that we produce ? Know this: a: Know that the carbon cycle involves a group of processes that move carbon from one area to another. b: Know that burning fossils fuels releases carbon dioxide in to the atmosphere. Friday 21 October 2011 Introduction: The Earth’s atmosphere, crust and oceans all contain carbon. The carbon cycle is a group of processes that move carbon from one area to another sometimes locked in solid or liquid form found deep underground, sometimes in gaseous form in the atmosphere. Millions of years ago the plants and animals that died got buried underground, over time these then got changed into fossils fuels. Combustion of these fossil fuels in power stations and in vehicles release about 3 billon tonnes of carbon dioxide into the atmosphere every year.

20. P2.10 a Look at the photograph and information and answer all the questions: The carbon cycle describes how carbon found in organic molecules, fossil fuels like coal and oil or in the air as carbon dioxide is cycled over time. Because humans are extracting fossil fuels like coal and oil from underground and then combusting them we are currently adding 3 billions tonnes of carbon (in CO 2 ) to the atmosphere every year. This is slowly warming our planet because the carbon dioxide molecules traps infra red energy from the sun. This effect is known as global warming. The carbon cycle Look at the diagram opposite left, it shows the carbon cycle. Which activity adds most carbon dioxide to the atmosphere which already contains 775 billion tonnes of carbon dioxide ? List three changes to the Word’s climate if atmospheric carbon dioxide continues to rise at the current rate of 3 billions tons a year ? Key concepts

21. P2.10 b Look at the photograph and information and answer all the questions: When fossil fuels are burned they increase the amount of carbon dioxide in the atmosphere. This can be taken back into the carbon cycle via photosynthesis and rain. However there are more processes that produce carbon dioxide than take it up. Power stations, cars and animals all produce a lot of carbon dioxide. Other than using fossil fuels how else can we generate electricity without adding CO 2 to the atmosphere ? List three other ways we can all reduce our carbon emissions ? Do you think we should ban flights between London ad Paris now we have Eurostar which takes the same time and produces less carbon dioxide ? Key concepts

22. P2.10 c Look at the photograph and information and answer all the questions: Cars combust fossil fuels like petrol inside a their engines. The resulting explosion provides the force to drive the car forwards. The average family car (1.4l 120 BHP 4 door hatchback) does about 12 kilometres per litre during an urban cycle. For every kilometre, the car releases about 250 grams of CO 2 . Over a year (based on 16,000 km) that a whopping 4 tonnes of CO 2 . A petrol driven car is about 20% energy efficient...look at the diagram, opposite how is most of the energy contained in petrol wasted ? A bus carrying 50 people produces almost 800 grams of CO 2 per kilometre. Despite this high figure explain why buses are more environmentally friendly than cars ? 30,000 kJ of chemical energy in one litre of petrol 6,000 kJ of kinetic energy Input energy Output energy 24,000 kJ of heat and sound energy Emissions of a petrol car Although an electric car does not produce any pollution where it is driven, explain why it is not a pollution free vehicle ? A family car (1.4l 120 BHP hatchback) produces about 250 grams of CO 2 for every kilometre and over a year doing 16,000 km a whopping 4 tonnes Key concepts

23. P2.10 Plenary Lesson summary: Decide whether the following statements are true or false : False True False True False True cycle carbon oceans atmosphere Our ‘carbon footprint’ is defined as the carbon we release in the form of carbon dioxide as a result of the energy that we use yearly. Currently in the UK it is around 5 to 6 tonnes of carbon dioxide per person per year. Most the carbon that we use is for transport and heating and lighting our homes. How Science Works: Friday 21 October 2011 Research into climate changes caused by global warming and increasing atmospheric carbon dioxide levels and what impact these climate changes might have on the World's population. Preparing for the next lesson: 3: Oil is a type of fossil fuel rich in carbon compounds ? 2: Plants take up carbon dioxide during photosynthesis safely locking it away ? 1: Power stations don’t produce carbon dioxide ? The Earth’s _________, crust and __________ all contain carbon. The carbon __________ is a group of processes that move _________ from one area to another. Currently human activity is shifting carbon form deep underground into the atmosphere.

25. P2.11 Changing climates ? Extension questions: 1: Imagine and leap forward in time by 50 years. You have a warmer World. How might the following change a) Human health, b) Our forests, c) Our farming d) competition for water and e) Our species biodiversity 2: Rising temperatures means rising sea levels. If you live in a coastal region what might happen to you ? 3: How do scientists predict what will happen to our climate next ? 4: Explain why will sea levels rise over the next fifty years? Know this: a: Know that carbon emissions will change the Earth’s climate through global warming. b: Know how we can reduce our carbon dioxide emissions. Friday 21 October 2011 Introduction: Carbon dioxide is one of the main greenhouse gases that causes climate change, however other factors can also cause climate change. These include a change in Earth’s orbit, a change in the sun’s radiation cycle and increase volcanic activity. Scientists have used computer models to predict how changing global temperatures will impact on Earth and its people and in particularly on Human health, agriculture and farming, forests, water resources, species and habitats and coastal area through rising sea levels.

26. P2.11 a Look at the photograph and information and answer all the questions: List three things that might affect life in the UK because of global warming ? If other places on Earth no longer supports human life because of global warming, what effect might mass migration have on rich countries ? Impact from global warming Farming Forestry Water Health Coastlines Habitats Global warming will have serious impacts on the environment and on society. Higher temperatures will cause a melting of ice. This will cause sea level to rise. The speed at which global warming is expected to occur is faster than most plant and animal species will be able to cope with. Global warming will affect agriculture. Water resources will also be affected. Global warming will also affect human health. Increasing air pollution in cities, reducing air quality. The malaria mosquito may also be able to spread to other regions of the world where it is currently too cold to survive and breed Key concepts

27. P2.11 b Look at the photograph and information and answer all the questions: An Inconvenient Truth is a documentary film about former United States Vice President Al Gore's campaign to educate citizens about global warming via a comprehensive slide show that, by his own estimate, he has given more than a thousand times. The documentary was a critical and box-office success, winning Academy Awards for Best Documentary Feature Was Al Gore right to make the documentary film ‘An Inconvenient Truth’ or did he dilute the science behind ‘global warming’ ? Look at the map opposite left it shows how certain area might be affected by failing crops, water resources, melting ice or even rising seas. Which areas are affected most ? How can we reduce our impact on the environment and reduce our carbon footprint ? Key concepts

28. P2.11 c Look at the photograph and information and answer all the questions: Do you think the UK and its people are equipped to cope with climate change over the next fifty years ? Are there any positives to climate change for us here in the UK ? How can climate change affect people from developing countries ? If the World climate changes in wealthy countries, the average cost would probably be small, although some people and regions might have high costs and others might receive large benefits. In some poor countries, the cost could be very high. A large or fast change in climate will have a big effect on plants and animals in the natural environment. Very rapid climate change is unlikely, but could be disastrous, even for wealthy countries. Key concepts

29. P2.11 Plenary Lesson summary: Decide whether the following statements are true or false : False True False True False True volcanic climate orbit carbon China is currently building 3 coal fired power stations every month. That’s a staggering 36 every year to meet its increasing energy demands. China has very few reserves of the ‘so called’ clean burning natural gas, Instead it is currently mining its huge coal reserves. Each power station will produce about 30 to 40 million tonnes of CO 2 every year ! How Science Works: Friday 21 October 2011 Research into the risk posed to the UK and its population if global warming caused climate change that led to the shutting down of the North Atlantic Drift. Also look at ways in which we may be able to reduce atmospheric carbon dioxide. Preparing for the next lesson: 3: Carbon dioxide has no effect on the climate ? 2: Scientists use computer models to predict the future ? 1: Volcanoes can change the earth’s climate ? Natural factors can cause ________ change, such as: Changing the Earth’s _______, changing the sun’s radiation cycle and _______ eruptions which can increase the earth’s ________ emissions.

31. P2.12 Time for action ? Extension questions: 1: List three ways or new laws that the government can reduce UK carbon emissions ? 2: How can you help to reduce carbon emissions in your daily life ? 3: Give an example of what the government has done already to reduce carbon emissions for example investing in public transport ? 4: Why will businesses find it hard to help climate change ? 5: How can this school help to reduce its carbon foot print ? Know this: a: Know that the government aims to reduce carbon emissions world wide. b: Know that businesses and people can help by reducing their carbon foot print. Friday 21 October 2011 Introduction: The government aims to reduce carbon emissions by 60% by 2050 ! They aim to do this by introducing new taxes, laws and regulations. However this may be difficult because people may feel their freedom is being taken away and businesses may have to fight to protect their profits, for example the congestion charge has affected many small businesses in Central London. Our lifestyles in the UK dependent on energy form burning fossil fuels. As a population are we prepare to halve our energy consumption. Energy we use to drive our cars, heat and light our homes and produce the goods and foods that we consume ?

32. P2.12 a Look at the photograph and information and answer all the questions: Northern Europe including the United Kingdom is warmed by the great currents know as the North Atlantic drift (NAD). This current brings warm waters all the way from Mexico and Miami across the great Atlantic and bathes the UK in warm water. Without these currents our winters would be much colder. Scientists believe the global warming may slow or even shut down these currents bringing disaster to the UK. Moscow is on the same latitude as London. During the winter Moscow’s temperature are about 10 o C below that of London...explain why ? Explain why are port remain ice free during the winter months ? What might happen to the UK’s plants and animals if the NAD shut down completely ? Key concepts

33. P2.12 b Look at the photograph and information and answer all the questions: Wind is moving air that has kinetic energy. This energy can be captured to drive a wind turbine generator. The blades are turned by the wind, which in turn makes a generator turn. This induces an electric current. Wind generators or farms are found in windy places like offshore. Although these wind farms don’t create pollution, many people object to how they spoil their view. Explain how a wind turbine can generate electrical energy ? Give three advantages and three drawbacks to using wind turbines rather than fossil fuel powered power stations? Why are the majority of wind farms here in the UK place offshore rather than on land ? Key concepts

34. P2.12 c Look at the photograph and information and answer all the questions: Generating electricity using renewable energy sources unlike burning fossil fuels produces no greenhouse gases or other pollution like acid rain. The UK government will aim to produce up to 20% of our energy using renewable technologies like wind, wave, tidal and solar energy. This will also reduce our dependence on fossil fuels. Why are renewable energy sources like tidal and wave power becoming more important as reserves of crude oil, gas and coal become less and less ? Explain how a tidal barrage can generate electrical energy ? Wave power uses energy created by winds acting on the sea, tidal power uses moving water as the result of ? Key concepts

35. P2.12 d Look at the photograph and information and answer all the questions: Saving energy makes good sense: It costs you less money, uses up less fossil fuels and reduces pollution of the environment. Both at work and at home, we can all save energy. Modern buildings are fitted with loft and wall insulation and double gazing. These innovations help reduce heat escaping through windows, doors, walls and ceilings. When you lay floor insulation it reduces heat loss from a heated room...does this floor insulation reduce heat loss through radiation, conduction or convection ? Explain how a kettle that can boil just enough water for one cup of tea can save energy when compared to kettles that boil a minimum of one litre of water ? Explain why turning down your thermostat at home by just 1 o C and wearing a jumper inside can save lots of money normally spent on central heating ? Key concepts

36. P2.12 Plenary Lesson summary: Decide whether the following statements are true or false : False True False True False True charge carbon taxes regulations In the UK we produce on average around 6 to 7 tonnes of carbon dioxide every year for every person. About 4 tonnes of that carbon dioxide is produced by cars burning fossils fuels. Fossil fuels used to heat and light our homes, schools, factories and offices accounts for about 1 tonne of carbon dioxide. Our energy hungry lifestyle is changing the atmosphere and consequently causing global warming. How Science Works: Friday 21 October 2011 Revise for an end of module test Preparing for the next lesson: 3: Carbon emissions can’t be reduced ? 2: People can’t help climate change ? 1: The government isn’t aiming to reduce carbon emissions ? The government aims to reduce _________ emissions by 60% by 2050! They aim to do this by introducing new ________, laws and _________. They have already done this by introducing the congestion _______.