Eureka moments

Educational resources

Introduction
Eureka moments – past, present and future

Health
Inspired by insulin
Science and sex
Cunning, devious, nasty

Environment
Skippy in the limelight
I'm gonna catch me a rabbit
Buzz off

Technology
Probing new worlds
Hazy wine and crazed cats
Use the light

Eureka moments – past, present and future

In general, science research progresses in a series of small, incremental steps, making advances over a period of time. However, sometimes there is a Eureka moment when the problem is suddenly solved.

This exhibition presents nine Eureka moments that have occurred over the past 50 years in the fields of health, technology and the environment. But there are many problems still to solve. One – the problem of salinity – is still waiting for its Eureka moment.

Salinity is a major scientific problem in Australia. It decreases agricultural production, affects water quality, threatens biodiversity and damages roads and buildings.

There are two kinds of soil salinity: dryland salinity (occurring on land not subject to irrigation) and irrigated land salinity. Both occur in areas where soils contain high levels of salt.

Much of Australia's landscape is naturally saline – think of the great salt lakes in our interior. Many of our agricultural lands also contain vast reservoirs of salt, but normally these are held deep within the soil profile where they don't affect plant growth. The problem occurs when this salt is brought to the soil surface by rising water tables.

Remote sensing is being used to map salt stores in the ground. These maps, combined with data from decades of field research, are helping scientists to understand how and where the salt is moving and to predict sites most at risk of salinisation.


Useful sites

Salinity – the awakening monster from the deep (Nova: Science in the news, Australian Academy of Science)

Monitoring the white death – soil salinity (Nova: Science in the news, Australian Academy of Science)

Introduction to remote sensing (PhysicalGeography.net, Canada)

Salinity mapping methods in the Australian context – conference proceedings
(17 October 2003, Australian Academy of Science)


Salinity information from each State


Discussion questions

  • How do you think salinity decreases agricultural production, threatens biodiversity and damages roads and buildings?

  • What areas of Australia are most threatened by salinity?

  • What do you think the terms groundwater and water table mean?

  • In some areas tree-planting is advocated as a method to reduce salinity. Why do you think planting trees would affect salinity?

  • Remote sensing is used to map salt stores in the ground. What is remote sensing?


Activities

  • Using the information available at Australia's salinity problem (National Action Plan for Salinity and Water Quality, Australia), write a short paragraph explaining what salinity is and the difference between dryland salinity and irrigation salinity.

  • Write a short explanation of the causes of soil salinity using the information available at Salinisation – causes and preventions (Nova: Science in the news, Australian Academy of Science). Include the terms groundwater, water table, recharge and discharge in your explanation.

  • Educational activities (Salinity – Australia's silent flood, Australian Broadcasting Corporation) has activities and case studies for each of the four episodes of the 2002 documentary series, The Silent Flood.

  • Caring for the country: Salinity of soils and water (NSW HSC Online, Charles Sturt University, Australia) provides resources and activities for this aspect of the Earth and Environmental Science syllabus.

  • Queensland Department of Natural Resources and Mines (Australia) provides two investigations into the effects of salinity on plant growth – Effects of soil salinisation and Threshold levels for cultivated crops.

  • University of Adelaide has two activities relating to salinity – Effect of salinity on beans and Determining soil texture.

  • Sad, salty pot plants (Country Areas Program, New South Wales Department of Education and Training, Australia) explains how to design an experiment to determine the effect of different concentrations of fertiliser on plants, and the relationship to salinisation.

  • Read What is remote sensing? (NASA, USA) and write a brief explanation of the technique in your own words.

Inspired by insulin

Injecting insulin is a daily routine for many. Without injecting insulin, people with diabetes are unable to convert the food they eat into energy. Their bodies cannot produce insulin, the hormone that transports glucose from the blood into body cells. To treat diabetes, insulin used to be sourced from the pancreas glands of pigs and cows. Some patients had an immune reaction to animal insulin so researchers looked to other methods.

The insulin that diabetics now use is an exact copy of the human hormone insulin produced by the pancreas. John Shine, a biochemist, was the first to show that a human gene could be copied and transferred into bacteria to produce a biologically active product. A number of human proteins and hormones can now be produced such as human growth hormone, immune molecules for treating cancer and enzymes to dissolve blood clots after heart attacks.


Useful sites

Professor John Shine interview (transcript of ABC TV's George Negus Tonight, 20 August 2003)

Professor John Shine (Faculty of Medicine, University of New South Wales, Australia)

Genetic engineering (British Broadcasting Corporation, UK)
Explains how to isolate and identify a gene and how to put the gene into another organism to be cloned.

Stem cells – gateway to 21st century medicine (Nova: Science in the news, Australian Academy of Science)

Humanity's heritage: The human genome and stem cells (An address by Professor John Shine to the National Press Club, 21 July 2004)

What is diabetes? (International Diabetes Institute)


Discussion questions

  • What do scientists mean when they say that genes act like a blueprint?

  • What is meant by cloning? What kinds of cloning are there?

  • What are stem cells?

  • Why do diabetics have to be careful about their diets?

  • Do you think it is better for diabetics to inject insulin that has been isolated from a pig's pancreas or to inject insulin that has been produced by a cloned human gene? Explain your answer.

  • What other human genes might be cloned in order to improve medical treatments?


Activities

  • Desperately seeking insulin (The University of Texas Health Science Center at San Antonio, USA)
    In this play students take on the roles of glucose, insulin, and organs in the body to demonstrate how our bodies process sugar.

  • Saving superman – a look into stem cell research (National Center for Case Study Teaching in Science, University of Buffalo, USA)
    This case study covers the main concepts of stem cell research and therapy and the political and ethical issues surrounding these subjects. Case study teaching notes are available.

  • New York TimesLearning Network, USA

    Variety is the spice of cellular life
    Reviews animal cell structure, explores the functions of stem cells and assesses ways in which stem cells might aid in treatments and cures.

    A new you!
    Learn how stem cells function and how they might help bodies heal

Science and sex

Take one pill once a day to control fertility. The development of the oral contraceptive pill was not the aim of chemist Arthur Birch. He refined a chemical reaction in 1950—now called the Birch Reduction Method—that allowed the activity of steroids to be modified. Today 70 million women across the world take the oral contraceptive pill. It is also the preferred contraceptive choice for 52 per cent of visitors to Australian Family Planning Clinics.


Useful sites

Arthur Birch, organic chemist (1915-1995)

Reduction and oxidation reactions (Chemtutor.com)

Steroids (Elmhurst College, USA)

The pill: Myths and misconceptions (Women's Health Queensland Wide, Australia)


Discussion questions

  • What is meant by the terms contraception and fertility?

  • One important use of the Birch Reduction Method is the modification of steroids. In what context have you heard of steroids?

  • Why do you think the expanding population poses a major challenge for our world?

  • A modified version of the hormone progesterone is the main component of the pill. What other hormones do you know about and what do they do?


Activities

  • Using library and internet materials, find out what is meant by a chemical 'reduction' and write a short definition.

  • Oxidation: How can it be proved? describes several experiments that illustrate oxidation.

  • Oxidation-reduction of indigo carmine demonstrates the use of dextrose as a reducing agent to change the colour of the indigo carmine to yellow.

  • Hormones of the reproductive system (Kimball's Biology Pages, USA) includes information about oestrogen and progesterone and how they work. Summarise how these hormones and their actions relate to the combined oral contraceptive pill.

  • Find out more about steroids and write a short report on what you have learned.

  • Write a short report summarising the information available at Contraception – past and future by Anna Glasier (Nature, October 2002).

  • Sanger, Pincus, Rock, Colton, Marker and Djerassi are other names associated with the development of oral contraceptives. Using library and internet resources, find out more about how each of these people contributed to the development of the pill, and then write a short report on what you have learned.

  • Human population (Population Reference Bureau, USA) provides a number of discussion questions and web resources related to the topic.

Arthur Birch, organic chemist (1915-1995)

Arthur Birch was born in Sydney on 3 August 1915. His interest in chemistry was evident as a child; his grandmother apparently called him 'Professor'. He studied organic chemistry at the University of Sydney, graduating with a University Medal in 1936. He travelled to England for his post-graduate studies, receiving a DPhil from the University of Oxford.

He continued his research in England until 1952, initially at Oxford then moving to the University of Cambridge in 1948. During this period he formulated a breakthrough procedure that became known as the Birch Reduction – one of the most widely used methods in synthetic organic chemistry. The procedure used alkali metals in liquid ammonia to reduce aromatic rings. Using the procedure, Birch made analogues of natural steroid hormones, which was a major contribution to the development of the oral contraceptive pill. This contribution has led to the description of him as 'the grandfather of the pill'.

Birch returned to Australia in 1952 to take up the position of Professor of Organic Chemistry at the University of Sydney, but remained here for only a few years. Frustrated by poor equipment and inadequate funding, he returned to the UK in 1955 as Chair of Organic Chemistry at the University of Manchester. He was lured back to Australia in 1967 when the Research School of Chemistry was established at the Australian National University in Canberra. He was appointed as Dean of Chemistry and Foundation Professor of Organic Chemistry, and held the latter position until his retirement in 1980.

Birch took a broader interest in science than just his own area of research. In particular he worked to strengthen scientific contacts between Russia and Australia.

Birch was elected as a Fellow of the Australian Academy of Science in 1954 (president 1982-86), a Fellow of the Royal Society in 1958 and was a Foreign Member of the Russian National Academy of Sciences. Just before his death in 1995, the main building of the Research School of Chemistry at the Australian National University was named the Birch Building.

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Cunning, devious, nasty

Viruses have challenged humans for centuries. The Spanish flu in 1918 killed 50 million people worldwide, including Australia—more than the number of deaths in four years of fighting during the First World War. Humans’ continual battle with invading viruses was given new armoury when Peter Doherty, an immunologist, described how our body’s immune system goes about recognising virus-infected cells. This led to an understanding of how the immune system distinguishes between the body’s own tissue and foreign organisms—‘self’ and ‘non-self’—and resulted in advances in vaccine development and increased understanding about transplants.


Useful sites

Interview with Professor Peter Doherty (Australian Academy of Science)

Peter C. Doherty – Autobiography (Nobelprize.org, Sweden)

The immune system (Back to Basics, Australian Academy of Science)

Nobel prizes: Unraveling immune-cell mysteries (Science Magazine, USA)

Understanding cancer series: The immune system (National Cancer Institute, National Institutes of Health, USA)

Immunisation – protecting our children from disease (Nova: Science in the news, Australian Academy of Science)

The Science of Immunisation: Questions and Answers (Australian Academy of Science)


Discussion questions

  • What is the function of your immune system?

  • How would you describe the difference between natural immunity and acquired immunity?

  • What are the characteristics of viruses? Why do you think it is difficult to find drugs to control viral diseases?

  • What do you think the term autoimmune means?

  • What do you understand about the term vaccine?

  • Why do you think some parents in the community are opposed to childhood immunisation?


Activities

  • Write a paragraph summarising the information at Vaccines explained (Better Health Channel, Australia).

  • Prepare a short talk on how vaccination provides immunity to a disease.

  • Choose a vaccine-preventable disease and find out more about it using library and internet resources. Combine your information with others in the class to create a table that shows symptoms, causes, methods and patterns of transmission, treatment, and prognosis for any of the diseases for which there is a current vaccine available.

  • Use library and internet resources to investigate which vaccines are currently recommended for people living in Australia and how this compares to recommendations for other countries. Present your findings as a brief report.

  • Student teams investigate both sides of the pro- and anti- immunisation argument. After collecting information, the class can have a debate on the question 'Is global immunisation a worthwhile objective?'.

  • The immune response (NSW HSC Online, Charles Sturt University, Australia) provides you with information about the immune response and has a number of suggestions to help learn more about immunity and vaccination.

  • Using balloons to teach immunology (American Association of Immunologists, USA)
    This participatory classroom demonstration can be used to show what antibodies look like and how they combine with foreign materials in order to eliminate them from the body. It illustrates several principles of immunology and can be modified for a variety of audiences.

  • Discovery School, USA

    • Operation antibody
      Students learn how the human immune system works at the cellular level. They identify what types of cells are important in the immune system and investigate the different mechanisms used by these cells.

    • Common vaccinations
      Students learn how vaccinations work and create class posters describing different types of vaccines.

  • Immunization (CyberSchoolBus, The United Nations)
    This site provides a wide range of information concerning how global immunisation programs are developed and implemented, and suggests number of classroom activities.

  • Immunotherapy is treatment that uses certain parts of the immune system to fight disease, including cancer. Write a paragraph or two summarising the information available at Types of immunotherapy (American Cancer Society).

  • Find out more about diseases that involve autoimmune reactions and write a short report on your findings.

Skippy in the limelight

Kangaroos, wallabies and platypus are known internationally for being cute, unique and a bit odd. Australia’s marsupials are also distinctive in the information they provide genetically. We learn more about the importance of various human genes by comparing them with those of other animals. Kangaroos are well placed to highlight genes of biological importance. Jenny Graves, a geneticist, is planning to sequence the first marsupial genome.

Useful sites

Interview with Professor Jenny Graves (Australian Academy of Science)

Teachers notes to accompany an interview with Professor Jenny Graves (Australian Academy of Science)

Reality CV – Jenny Graves (Women in Science Enquiry Network, Inc, Australia)

Kangaroo – The goldilocks genome (transcript of The Science Show, 28 September 2002, Australian Broadcasting Corporation)

Fact sheets from the National Human Genome Research Institute (National Institutes of Health, USA)

Discussion questions

  • What are the differences between marsupials and other mammals?

  • What does it mean when scientists say that kangaroos are our distant relatives?

  • Why do you think it might be more important to sequence a marsupial genome than a frog genome?

  • How could the identification of special marsupial genes lead to new human drugs?

  • Why do genes need to be turned off and on at different times?

  • How do you think the Kangaroo Genome Project could help protect Australia's biodiversity?


Activities

  • Build your own DNA model (Double Helix, CSIRO, Australia) provides templates for you to assemble a DNA model.

  • Number the following in order of their size in an organism, from smallest to largest:
    genome DNA gene base chromosome

  • Read The Kangaroo Genome Project (Australian National University) and then prepare a news report that describes the project and what it hopes to achieve.

  • Biotechnology Australia

    • Extracting DNA in your kitchen describes how to extract DNA from onion cells.

    • DNA sequencing provides a sequence of coloured bands from electrophoresis. Using this information, you can work out the sequence of bases in a section of DNA.

    • Using a gene probe is an interactive online activity in which you can work through the steps of extracting a cell and treating the DNA in it, and then use a gene probe to find out which of the organism's chromosomes carries a particular gene.

  • Read Gene mapping and DNA sequencing (Nova: Science in the news, Australian Academy of Science) and write a paragraph or two explaining the difference between mapping and sequencing a genome, and the difference between a genetic map and a physical map.

  • Sequence for yourself (NOVA, Public Broadcasting Service, USA) does a good job of describing, with diagrams, the complex method used to determine the sequence of bases in a genome. Upper level students can attempt to summarise the sequencing method in their own words.

I'm gonna catch me a rabbit

European rabbits became a pest, then a plague and a personal enemy to Australian farmers after being introduced for sport in 1859. Burrowing through pastoral and cropping land, they stripped bushes of leaves and bark and left the environment vulnerable to erosion. The population was initially kept in check by trapping, shooting, baiting, poisoning and gassing. With no natural predator though, they reached plague proportions. Something had to be done.

Frank Fenner was the virologist on the team who released the myxoma virus, a virus specific to European rabbits, into the Murray River Valley in 1950. Within two years the rabbit population dropped from 600 million to 100 million. There was also a subsequent increase in wool and meat production worth $68 million due to recovered pastures.


Useful sites

Interview with Professor Frank Fenner (Australian Academy of Science)

Teachers notes to accompany an interview with microbiologist and virologist, Professor Frank Fenner (Australian Academy of Science)

Frank Fenner (transcript of ABC TV's George Negus Tonight, 17 February 2003)

2002 Prime Minister's Prize for Science – Professor Frank Fenner (The Department of Innovation, Industry, Science and Research, Australia)

A plague on the pest – rabbit calicivirus disease and biological control
(Nova: Science in the news, Australian Academy of Science)

Commonwealth Department of the Environment and Heritage, Australia

Dr Laurie Twigg (run, rabbit, RUN! – the story of rabbits in Western Australia Australian Museums and Galleries Online)
Transcript of a 2002 interview with Dr Laurie Twigg from the Vertebrate Pest Research Services in Western Australia. Covers different methods of rabbit control.

Discussion questions

  • Why do you think rabbits became plague after they were introduced into Australia in 1859?

  • What does the term 'biological control' mean?

  • Why do you think there is still a rabbit problem in some parts of Australia even though the myxomatosis was very effective in reducing rabbit numbers?

  • There are many vertebrate pest species in Australia in addition to the rabbit (eg, fox, mouse, carp, cane toad, feral pig). Which of these species do you think would be the most important to control? Explain your answer.


Activities

  • Using the information available at Rabbits (Invasive Animals CRC, Australia) and European rabbit (Oryctolagus cuniculus) (feral.org.au) write a short report explaining why rabbits are Australia's most widespread and destructive pest animal.

  • Find out more about myxoma virus and the more recently introduced rabbit calicivirus. Write a report comparing the two viruses, including mode of transmission and type of genetic material.

  • Use role play to simulate a meeting of concerned people in an area where rabbits are a problem. Representatives could include a grazier, an animal liberationist, a geneticist, a politician, an environmentalist, a zoologist or botanist, and a veterinarian.

  • Nova: Science in the news (Australian Academy of Science)

  • How do we get rid of pests? (Tall Poppy Campaign, Australian Institute of Political Science) provides information and classroom activities relating to rabbits in Australia.

  • run rabbit RUN! (Australian Museums and Galleries Online) covers the story of rabbits in Western Australia. Using the information available at this site, explain in your own words how rabbits affect native plants and animals and agriculture.

  • Viruses and host evolution (Access Excellence, USA) introduces viruses and their effects on the evolution of rabbit populations. Students then find out more about a viral disease of their choice.

  • Rabbit calicivirus disease: Magic bullet or Pandora's box? (University at Buffalo, The State University of New York, USA)
    Students read a scenario about a proposed release of rabbit calicivirus disease in New Zealand as a biological control, and then discuss the questions that are provided. Teachers' notes are available.

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Buzz off

Outdoor living in Australia is synonymous with insects – flies, mosquitoes and ants. Called into action during the Second World War, Douglas Waterhouse, an entomologist, discovered the active ingredients of insect repellent, a now permanent fixture in any picnic basket, camping backpack and sporting bag.


Useful sites

Interview with Dr Douglas Waterhouse (1916-2000) (Australian Academy of Science)

Teachers notes to accompany an interview with Dr Doug Waterhouse (Australian Academy of Science)

Biographical memoirs of Douglas Frew Waterhouse (Australian Academy of Science)

Integrated pest management – the good, the bad and the genetically modified
(Nova: Science in the news, Australian Academy of Science)

Crops and pest control by James Ridsdill-Smith
(Nature and Society Forum, Australia)


Discussion questions

  • What is the difference between a repellent and a pesticide?

  • What is biological control? Why do you think biological control methods might be preferable to using pesticides for insect control?

  • Australia was certified free of malaria by the World Health Organization in 1981). Why do you think occasional cases of malaria are still reported in Australia?

  • What do you think is meant by the phrase integrated pest management?

  • What are some methods employed in integrated pest management?


Activities

  • Bugs (Museum Victoria)
    Waterhouse was an entomologist, someone who studies insects. This website tells you all about bugs, many of which are insects. Find out about different types of bugs in the museum's collection at Bugcatcher (Requires Flash 6 Player). Check out the Classification guide and try some of the Activities on the Education page. The activities cover Prep-Year 2, Years 3-6, and Years 7-10.

  • Read the 'Pest origins' section of Insects as pests (University of Sydney) and then summarise the information in a paragraph.

  • Summarise the information on malaria and its prevention available at Protozoa: malaria (schoolscience, UK) (There is a short quiz available.)

  • Malaria is characterised by recurring bouts of fever every few days, with no significant symptoms in between. How does this cycle of symptoms relate to the life cycle of the malarial parasite?

  • Biological control vs pesticides (Center for Insect Science, University of Arizona, USA) has students design and perform a controlled experiment to assess the effects of predators and insecticides on a population of insect pests.

  • Nova: Science in the news (Australian Academy of Science)

  • Global Education (AusAID, Australia)

  • Read the case study at To spray or not to spray: A debate over malaria and DDT (National Center for Case Study Teaching in Science, University of Buffalo, USA) then discuss the questions provided. Case teaching notes are available.

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Probing new worlds

For millennia we explored the Universe only by what we can see— visible light. In the twentieth century astronomers started using other tools such as UV radiation, X-rays and radio waves. They uncovered an invisible world. The discovery by three engineers, headed by John Bolton, of the first extragalactic radio sources soon after World War II revolutionised space exploration. Mapping the skies using radio waves means we can probe more deeply into the universe.


Useful sites

Biographical memoirs of John Gatenby Bolton (1922-1993) (Australian Academy of Science)

From the solar corona to clusters of galaxies: The radio astronomy of Bruce Slee (Publications of the Astronomical Society of Australia, 2004, Vol. 21)

Vale Gordon Stanley (by Wayne Orchiston and Bruce Slee) (Australia Telescope National Facility, CSIRO, Australia)

Australia Telescope National Facility, CSIRO, Australia

The future of radio astronomy (Australian Broadcasting Corporation)


Discussion questions

  • Why do you think it is important to study astronomy?

  • How would you describe 'radio astronomy'?

  • What is 'outer space'?

  • Some scientists use radio telescopes to 'listen' for signals that might have been produced by intelligent life elsewhere in the universe. What do you think these scientists have to consider when setting up their investigations?


Activities

  • Watch the short video, Hidden galaxies, from the CSIRO's Australia Advances series and then write a report to show what you have learned about radio telescopes and finding new galaxies. (Requires QuickTime player.)

  • The one-square-kilometre telescope – the future of radio astronomy (Australian Broadcasting Corporation)
    Explores past conquests, exciting experiments and the future of radio astronomy. Contains numerous in-text links for finding out about ideas presented in the article. This site also has an Activities section containing numerous suggestions for additional ways to explore the material presented in the article, and a Teachers' guide.

  • Make a radio image (National Radio Astronomy Observatory, USA) explains how scientists turn radio data into pictures and provides real data for you to produce a 'radio picture'. Another activity, Be an interference detective, explains how you can use a small radio to detect radio waves given off by batteries and other appliances in your home.

  • The communications lab (AstroCappella, USA) shows you how to build and test a parabolic-dish receiver. This is the type of system used by radio telescopes to capture signals from space.

  • SETI – the Search for Extraterrestrial Intelligence – involves the use of large radio telescopes to detect radio signals from other intelligent civilisations. How SETI works (How Stuff Works, USA) describes SETI and How does SETI@home work? explains how you can donate some of your computer's time to the project by downloading software available at SETI@home.

Hazy wine and crazed cats

Your glass of sparkling white wine has been tested to ensure that it is absolutely clear. The presence of metal atoms can cause haziness, which winemakers test for using an atomic absorption spectrometer. In 1956 in Minamata, Japan, cats started frothing at the mouth, throwing fits and eventually suicided by jumping into the sea. Spectrometry revealed mercury had contaminated the fish that the cats—and people—had eaten.

The ability to detect the presence and concentration of small amounts of metal in any sample was made possible by Alan Walsh’s experiments with atomic absorption. The atomic absorption spectrometer can quickly and accurately detect what elements are in a sample of soil, metal, water or food. They are now found in virtually every hospital, laboratory and factory around the world.


Useful sites

Biographical memoirs of Alan Walsh (1916-1998) (Australian Academy of Science)

Atomic absorption spectroscopy (The Chemistry Hypermedia Project at Virginia Tech, USA)

Atomic absorption spectroscopy (University of Adelaide, Australia)

Flame atomic absorption spectrometry (Environmental Sampling and Monitoring Primer, Virginia Polytechnic Institute and State University, USA)


Discussion questions

  • Why do you think atomic absorption spectroscopy has been described as 'the most significant advance in chemical analysis' in the twentieth century?

  • What do you think is meant by the term 'trace elements'? Why are they important?

  • Sir Alan Walsh was well known and respected in scientific circles as the inventor of the atomic absorption spectrophotometer. Although his invention influenced everyone's lives, he was little known outside the scientific community. Do you think that today's public would know very little about an equivalent inventor? Defend your answer.

  • What do you think is meant by the terms 'emission' and 'absorption'?

  • What are some ways of expressing concentrations?


Activities

  • Chemical monitoring and management: Manufactured products are analysed (NSW HSC Online, Charles Sturt University, Australia) provides information about analysing the chemical composition of products. It provides several flow charts that can be used to assist in the identification of ions present in an aqueous sample, a case study on the monitoring of arsenic and a simplified diagram of the equipment used in atomic absorption spectroscopy.

  • Flame tests (NASA's Imagine the Universe, USA) explains how to observe and identify elements based on the color produced in a flame test.

  • Choose an element whose concentration can be measured using atomic absorption spectroscopy. Using library and internet resources, find out how measuring the concentration of that element is applied to a practical situation.

  • Atomic absorption spectroscopy has found important application worldwide in areas as diverse as medicine, agriculture, mineral exploration, metallurgy, food analysis, biochemistry and environmental monitoring. Choose one of these areas and find out how atomic absorption spectroscopy is used.

  • Absorption spectroscopy (Kansas State University, USA) has an interactive demonstration which allows you to observe the absorption spectra of different gases. (Requires Shockwave.)

  • One in a million (US Environmental Protection Agency) explains how to do a dilution series using mouthwash and then to calculate the concentration of each dilution in parts per million.

  • Parts per million (University of Nebraska-Lincoln, USA) explains the concept of parts per million and provides instructions for a serial dilution experiment using red food colouring that is analysed using a spectrophotometer.

  • Write a short paragraph explaining why atomic absorption spectroscopy has been particularly important in the analysis of trace elements. Include an example in your discussion.

  • Plants require a number of nutrients for productive growth, including the trace elements boron, iron, manganese, zinc, copper, molybdenum and chlorine. Using library and internet resources, find out more about one of these trace elements and plant growth (for example, the required concentration of the element, why the plant needs it, symptoms that appear if the plant is deficient or oversupplied). Write a report on your findings.

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Use the light

Too much to download, not enough time? Using the speed of light to transmit information via an optical fibre led to a breakthrough in communication capacity in the early 1990s. Allan Snyder, a physicist, explained exactly how light travels down a fibre, what dimensions the fibre needs to be and how to convert the pulses into information at the other end. His description simplified an existing theory, which laid the foundation for fibre optic technology.


Useful sites

1997 Australia Prize – Professor Allan Snyder (Department of Innovation, Industry, Science and Research, Australia)

Allan Snyder (Tall Poppy Campaign, Australian Institute of Political Science)

Communicating with light – fibre optics (Nova: Science in the news, Australian Academy of Science)

How fibre optics work (How Stuff Works, USA)

Modern communication: The laser and fiber optic revolution (Beyond Discovery, National Academy of Sciences, USA)


Discussion questions

  • What do you think is meant by the term 'fibre optics'?

  • Using light to transmit information via an optical fibre led to a breakthrough in communication capacity in the early 1990s. Before that, what methods were used to communicate over long distances?

  • In what ways has this increase in communication capacity affected your life?

  • Optical fibres are not used just for communication. What other uses are there for optical fibres?

  • Allan Snyder, a physicist, was studying how photoreceptors in the human eye transmit light images to the brain when noticed the transmission properties were similar to those of optical fibres. Today he is studying creativity through the Centre for the Mind. What characteristics do you think enables Snyder to work in such disparate fields?


Activities

  • In 1997 Allan Snyder, Rodney Tucker and Gottfried Ungerboeck were awarded the Australia Prize for their contribution to telecommunications. Using internet resources, find out more about the work of these three scientists and write a short report.

  • Nova: Science in the news (Australian Academy of Science) has two activities relating to fibre optics and communication with light. Optical fibres as 'light pipes' shows how light travels through a bent glass rod and Illustrating the inverse square law of radiation shows how illumination varies with distance from the light source.

  • Light water (CSIRO) has a do-at-home activity that demonstrates properties of optical fibres.

  • Telecommunications (Newton's Apple, USA) provides an introduction to telecommunications and activities on optical fibres.

  • Read the information available in the eight sections of the information kit The story of communications by light beam (Telstra, Australia) and write a short report on what you have learned.

  • NSW HSC Online (Charles Sturt University, Australia)

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