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Rocket Science Secondary Schools Resource Pack Welcome to Rocket Science In December 2015 Tim Peake will leave Earth to live and work on the International Space Station (ISS). British astronaut Tim was selected for his mission in May 2013. His selection followed an increase in Government investment in the European Space Agency, and a first time ever investment by the British Government in the ISS programme. Principia, the name of Tim’s mission, honours the great work of Sir Isaac Newton, which laid down the laws of gravity and motion that are key to the world of space environments and human spaceflight. At his temporary home in space Tim will embark on his own programme of scientific discovery. The ISS is above all a place for scientific research, and while there Tim will be working on experiments that cannot be done anywhere on Earth. To mark Tim’s mission, the UK Space Agency has initiated a range of inspiring projects for schools. The projects harness the expertise of partner organisations in a wide range of fields. All projects have some element of science or technology in them, cover a range of curriculum-linked activities and use the mission to inspire young people and increase interest in STEM subjects. Everyone can be a space biologist! For Rocket Science, the UK Space Agency has teamed up the Royal Horticultural Society (RHS) Campaign for School Gardening to encourage students to become space biologists. On 2 September 2015, two kilograms of Rocket seed (Eruca sativa) travelled from Bailkonur, Kazakhstan on the Soyuz 44S rocket to the ISS. The seeds are being stored in microgravity aboard the ISS for six months before returning to Earth in the spring of 2016. Once returned to Earth, the seeds will be distributed to up to 10,000 UK schools along with seeds of the same batch that have remained on Earth. The seeds will be sown and grown side by side over 35 days, with schools observing, measuring and recording similarities or differences in growth. At the end of the experiment, schools will enter their results in a national database and findings will be published, thereby contributing to the knowledge bank scientists have been building since the beginning of spaceflight 50 years ago. If you have not already applied for your seeds please go to the RHS Campaign for School Gardening website. Royal Horticultural Society Reg charity no. 222879/SC038262 1 Join us in our mission to discover the vital role of plants in space The new Secondary Science curriculum encourages students to recognise the power of rational explanation and to develop a sense of excitement and curiosity about natural phenomena. The new Secondary Science curricula encourages students to recognise the power of rational explanation and to develop a sense of excitement and curiosity about natural phenomena. Students also learn to appreciate the relevance of science to their everyday lives. insects for pollination - are either absent or reduced in a space environment. Plants grown on Mars would be subjected to dust storms, freezing temperatures and harsh radiation. So over the last fifty years, space biologists have been finding out ways to compensate for these differences to see how plants could flourish. Rocket Science gives students the opportunity to take part in a live, practical, science experiment to explore the fascinating world of plants through the eyes of a space biologist. In our Rocket Science Secondary Resource Pack you will find three activities that will help you and your students have fun with plants and space, whilst considering the potential for our long term survival there. The resources have been designed to support learning in plant science, maths and human nutrition. One activity particularly concentrates on genomics and the effects of radiation on plant life in space. In space, as is the case here on Earth, plants will be vital for human survival. Plants provide the food that we eat and are a source of essential vitamins and minerals to keep us healthy. They absorb carbon dioxide and give us oxygen to breathe. In the world’s poorest countries, they can account for 90% of human needs; food, fuel, medicine, shelter and transportation. The activities have been designed to take between one and three lessons. Although we have recommended activities by age group/key stage, each can be adapted to suit a group of different ages with similar skills. Teacher, technician and pupil resources are available for each activity. People needs plants in space – and plants need people! Plants need all our ingenuity, scientific knowledge and skills to help them survive in really inhospitable conditions. All the things we take for granted on Earth - light, water, soil, gravity and Activity 1 Activity 2 Growing food for space exploration Healthy eating for space travellers 2 Activity 3 Hazards of space travel: modelling mutation in seeds with Rabidops Challenges to growing and eating in space Eating enough fresh food Food tastes different in space. Flavours are dulled leading to astronauts suffering from ‘menu-fatigue’ and craving food that is spicier and tarter than they would prefer on Earth. This is not helped by the physiological changes astronauts undergo in space, making it difficult for them to smell their food. Dieticians have pushed for more fresh food in astronauts’ space diets. How could they achieve this? Astronaut Kjell Lindgren opens a supply of fresh fruit Growing plants in space Some space bound plant growth experiments are already being conducted here on Earth in an environment that mimics space conditions. Scientists also work side by side with astronauts and train them to perform certain experiments whilst they are in space. In 1982 Valentin Lebedev, a Russian cosmonaut, was the first to grow an Arabidopsis plant through it’s entire life-cycle in space in a laptop sized greenhouse called Fiton. This breakthrough was the first indication that humans could grow their own food in space without having to transport new seeds from Earth. From 2002 to 2011 a series of experiments were conducted using the Lada greenhouse on the Russian segment of the International Space Station. Developed on Earth in 2006 by the European Space Agency, MELiSSA (Micro-Ecological Life Support System Alternative) is a five compartment system that harnesses the power of plants to break down human waste and provide water and fertiliser to grow healthy food crops. The crew themselves form an important part of the cycle providing MELiSSA with waste and water filtered from the crew’s urine. A key component of the MELiSSA system is Spirulina, a blue green algae harvested from the oceans. Spirulina can recycle carbon dioxide breathed out by the crew into fresh oxygen via photosynthesis. It also has spectacular nutritional properties and is sold dried in health food stores. The ultimate end product from MELiSSA is food suitable to sustain astronauts on long term missions. Red Romaine lettuce growing in Veggie on board the ISS Astronauts are currently working with plants in the Columbus Laboratory aboard the ISS. Veggie, developed by NASA, is a low cost plant growth chamber that uses a combination of red, blue and green Light Emitting Diodes (LEDs) so that plants can grow in an alternative to natural daylight. Red Romaine lettuce has been grown under LED lights on board the International Space Station since May 2014 and astronauts were finally able to snack on their space grown lettuce on the 10th August 2015. To extend your knowledge visit these websites; RHS, RHS Campaign for School Gardening, UK Space Agency, European Space Agency 3 Astronauts enjoy their first taste of space grown lettuce on board the ISS Growing plants on Mars The Martian climate is a challenging one; it is harsh and exposure to ultraviolet radiation will cause severe damage any living organism. Plants need air, light, warmth, water and nutrients to be healthy. If they are healthy, they can continue making their own food through photosynthesis. Thanks to NASA’s recent Mars exploration we know that there is water on Mars and some of it is at the surface. Features called ‘recurring slope lineae’ – dark lines that appear on Mars seasonally – have been shown to have salts from briny water associated with them. This means that water is in its liquid form and is flowing on the surface of Mars today. According to NASA, the probable mechanism enabling liquid water to exist is a process called deliquescence where the salts absorb water from the atmosphere and then form a liquid solution. On Mars there is 62.5% less gravity than on Earth. Even in this reduced gravity there is evidence that plant roots could find their way down into soil or growing media. If there are regions near the surface of Mars where life could exist and these can be protected from radiation, suddenly the prospect for life gets a lot better. Although the water on Mars appears to be very salty, we know of ‘extremophiles’ - organisms with the ability to thrive in extreme environments - that could thrive in facilities such as hydrothermal vents. Knowing if these organisms are able to live in very salty environments could be a step forward to make growing plants on Mars a reality. These pictures show evidence of historic water activity on the surface of Mars. Martian surface False colour view 4 Summary of Activities and Curriculum links Growing food for space exploration: The idea of needing to grow food to support space exploration is introduced, along with some of the challenges associated with growing plants in space. Students plan and carry out an investigation to measure germination rates in soils with different particle size, and relate their findings to the soils found on Mars and the Moon. Country Level / KS England KS3 Working Scientifically • A sk questions and develop a line of enquiry based on observations of the real world, alongside prior knowledge and experience • M ake predictions using scientific knowledge and understanding • S elect, plan and carry out the most appropriate types of scientific enquiries to test predictions, including identifying independent, dependent and control variables, where appropriate Combined science GCSE subject content (DfE) Working Scientifically • Carry out experiments appropriately having due regard to the correct manipulation of apparatus, the accuracy of measurements and health and safety considerations • Present observations and other data using appropriate methods Subject content - explain how some abiotic and biotic factors affect communities. Subject content - Plants making carbohydrates in their leaves by photosynthesis and gaining mineral nutrients and water from the soil via their roots. Northern Ireland Developing pupils’ Knowledge, Understanding and Skills Develop skills in scientific methods of enquiry to further scientific knowledge and understanding: • Planning for investigations, • Obtaining evidence, • Presenting and interpreting results Developing pupils as Individuals Spiritual Awareness - Develop a sense of wonder about the universe, for example, the scale from the smallness of the atom to the vastness of outer space, the complexity, diversity, and interdependence of living things etc. Scotland Inquiry and investigative skills • O bserve, collect, measure and record evidence, taking account of safety and controlling risk and hazards Scientific analytical thinking skills • Making predictions, generalisations and deductions Wales Enquiry – Planning The number of observations or measurements that need to be made and their range and values to ensure reliability of evidence. 5 CCEA GCSE Science (Double award) • Collection and analysis of scientific data; • Interpretation of data, using creative thought, to provide evidence for testing ideas and developing theories. • Complexity, diversity, and interdependence of living things etc. • CCEA GCSE Science (Double award) • Collection and analysis of scientific data; • Interpretation of data, using creative thought, to provide evidence for testing ideas and developing theories. Experiences and Outcomes Third By using my knowledge of our solar system and the basic needs of living things, I can produce a reasoned argument on the likelihood of life existing elsewhere in the universe. Fourth By researching developments used to observe or explore space, I can illustrate how our knowledge of the universe has evolved over time. WJEC Science GCSE • Make measurements/collect data. • Know that individual organisms have a need for resources from their environment e.g. food, water, light and minerals and understand that the size of a population may be affected by competition for these resources along with predation, disease and pollution. Summary of Activities and Curriculum links Healthy eating for space travellers: A basic space diet will need supplementing with vitamins if astronauts are to remain healthy for extended periods of time. In this activity students compare the vitamin C content of different plants to decide which should be grown in space to supplement the astronaut’s diet. Country Level / KS England KS3 Working Scientifically • A sk questions and develop a line of enquiry based on observations of the real world, alongside prior knowledge and experience • Make predictions using scientific knowledge and understanding • S elect, plan and carry out the most appropriate types of scientific enquiries to test predictions, including identifying independent, dependent and control variables, where appropriate Combined science GCSE subject content (DfE) Working Scientifically • Carry out experiments appropriately having due regard to the correct manipulation of apparatus, the accuracy of measurements and health and safety considerations • Present observations and other data using appropriate methods Subject content - explain how some abiotic and biotic factors affect communities. Subject content - Plants making carbohydrates in their leaves by photosynthesis and gaining mineral nutrients and water from the soil via their roots. Northern Ireland Scotland Developing pupils’ Knowledge, Understanding and Skills Develop skills in scientific methods of enquiry to further scientific knowledge and understanding: • Planning for investigations, • Obtaining evidence, • Presenting and interpreting results Developing pupils as Individuals Inquiry and investigative skills • O bserve, collect, measure and record evidence, taking account of safety and controlling risk and hazards Experiences and Outcomes Third By using my knowledge of our solar system and the basic needs of living things, I can produce a reasoned argument on the likelihood of life existing elsewhere in the universe. Fourth By researching developments used to observe or explore space, I can illustrate how our knowledge of the universe has evolved over time. Scientific analytical thinking skills • Making predictions, generalisations and deductions Wales Interdependence of organisms How food is used by the body as fuel during respiration and why the components of a balanced diet are needed for good health. Spiritual Awareness - Develop a sense of wonder about the universe, for example, the scale from the smallness of the atom to the vastness of outer space, the complexity, diversity, and interdependence of living things etc. CCEA GCSE Science (Double award) • Collection and analysis of scientific data; • Interpretation of data, using creative thought, to provide evidence for testing ideas and developing theories. WJEC Science GCSE Find patterns/relationships in data. • Understand that health is affected by a variety of factors and that science and technology may provide the answer to some health problems. • Understand that some treatments may involve risk-benefit assessments. 6 Summary of Activities and Curriculum links Hazards of space travel: Modelling mutation in seeds with Rabidops. This activity introduces mutation as a naturally occurring phenomenon that can be useful in producing new varieties of plant and animal. In space the chances of mutation are much higher than in Earth’s atmosphere. In this introductory activity students observe, record, and if possible explain the effects of mutation on a plant species through a modelling activity. Templates and sample data are provided to support two versions of this activity. Version 1 looks at the effect of mutation on six characteristics. Version 2 may be more appropriate if short of time or if you need to reduce the challenge for students. Country Level / KS England KS3 Working Scientifically • U se a variety of models such as representational, spatial, descriptive, computational and mathematical to solve problems, make predictions and to develop scientific explanations and understanding of familiar and unfamiliar facts • E valuate risks both in practical science and the wider societal context, including perception of risk in relation to data and consequences. Subject content - Describe simply how the genome, and its interaction with the environment, influence the development of the phenotype of an organism. Developing pupils’ Knowledge, Understanding and Skills Research scientific information from a range of sources; The solar system and universe. 2.7.2 Understand that mutations are random changes in the: - Number of chromosomes (Down’s Syndrome); or - Structure of genes and can be triggered by environmental factors, such as UV light causing skin cancer. Northern Ireland CCEA GCSE Science (Double award) • M any phenomena can be explained by developing and using scientific theories, models and ideas; • T he use of contemporary scientific and technological developments and their benefits, drawbacks and risks; Scotland Inquiry and investigative skills • P resent, analyse and interpret data to draw conclusions Scientific analytical thinking skills • Being open to new ideas and linking and applying learning Wales Enquiry – Planning Linking the learning to dissimilar but familiar situations, within and outside school. Recall that all variants arise from mutations, and that most have no effect on the phenotype, some influence phenotype and a very few determine phenotype. Experiences and Outcomes (CfE) Fourth I can use my understanding of how characteristics are inherited to solve simple genetic problems and relate this to my understanding of DNA, genes and chromosomes. WJEC Science GCSE Effect of/on society Developments in science and technology are useful for society but in a context of the risk management of consequential effects. • U nderstand that new genes result from changes, mutations, in existing genes and that mutations occur at random. • Most mutations have no effect but some may be beneficial or harmful. • Mutation rates can be increased by ionising radiation. 7 Growing food for space exploration 8 Estimated time: Three weeks (One lesson week one, and two half lessons in weeks tw o and three) Location: Laborat ory or greenhouse School term: All ye ar round Level of Experienc e: No prior experience requir ed Subject(s): Science, Technolog y & Maths Age group: 11-16 Growing food for space exploration Technical & Teaching Notes Outline Soils on the Moon and on Mars have different compositions to those found on Earth Students plant seeds on different media to simulate different soil types and calculate germination rates over two weeks Further activities are suggested that look at an alternative method of assessing healthy growth, and for comparing different artificial light sources for plant growth Learning outcomes Make predictions using scientific knowledge Make and record observations over time Suggest scientific solutions, including the use of technology, to problems of the growing human population Apparatus For each small group of students: Compartmentalised seed trays – 5x2 compartments Tray in which to place seed tray for drainage and ease of transport Horticultural silver sand 500g Modelling clay – finely crushed (take care with dust). Alternatively source clay with inert fine particles 500g Access to top pan balance Plant labels + pen/pencil Containers and spoons for mixing different proportions of sand and clay Seeds – such as rocket or ‘microgreens’ such as broccoli that can be planted indoors throughout the year and are fast germinating – about 100 seeds. Each group will need to leave their seed tray in a well-illuminated position (but out of direct sunlight to avoid drying out) at room temperature for up to two weeks. They should not need to water their seed tray once set up. A greenhouse would be ideal or a side bench in a lab where the seed trays can remain undisturbed. 9 Introduction and context Moon and Mars soils have been analysed and found to consist of different average particle sizes but both are a type of loose dusty soil called regolith. Scientists have created artificial Moon and Mars soils from volcanic dust, based on research information from space exploration. They found that plants grew well on both artificial soil types here on Earth, but that ‘Mars soil’ was especially good and contained a good supply of the minerals needed by plants. These artificial space soils are called ‘regolith simulants’. In the context of needing to grow crops on planets if astronauts are to survive, students investigate the effect of soil particle size on germination rates and percentage germination. In addition to differences between growth substrate and its mineral content, students should be aware that differences in temperature, radiation levels, reduced gravity, composition of the atmosphere, and absence of other organisms, whether pests or symbionts, are all going to have effects that are difficult to quantify. It is most likely that plants grown in space for the foreseeable future will be grown in artificial enclosures using hydroponics, rather than in soil. A collection of images and videos has been provided with this resource to enable students to identify features of Martian and lunar landscapes. The Sciences and Technology Facilities Council (STFC) have a collection of moon rocks available for loan to schools. A reference is provided to an article on regolith simulants at the end of this document. Teaching Notes - Lesson 1 To prepare the clay, create flattened saucer sized discs of clay, dry them out and crush to a powder and then sieve. Use a well-ventilated space (or face mask) when handling clay to avoid inhaling fine particles. Students need to be warned of the hazards associated with micro-organisms in soil. The particle sizes of different clay and sand proportions can be checked by students using a microscope, or by photographing using a jewellers lens attached to a mobile phone camera. The activity suggests that students make up a range of artificial soils with different proportions of small and large particles, using horticultural sand and clay. Modelling clay is a readily available source of fine particles. Students plant seeds on their soils and monitor the proportion of seeds that germinate over a ten day period. The percentage germination and speed of germination provide evidence when assessing if particle size influences plant growth. The procedure assumes that students will make decisions about the number of soil samples to use and the relative proportions of sand and clay to be used. This procedure could be simplified by providing students with seed trays that have already been prepared with soil samples. Below are images of sand (left) and clay (right) soils to show differing particle sizes. The soil samples were photographed using a mobile phone with microscope attachment. 10 Image to show seed tray set up with two rows of five different soil compositions. The sandier soils are to the left. Lesson 2 and 3 These lessons will be used to record seedling growth over a period of time 5-10 days. The students can decide their own methods of recording i.e. measuring height or number of leaves. From the results collected so far, seeds germinate more quickly on a mixture of sand and clay than on clay or sand alone. Once germinated some seedlings have difficulty in supporting themselves on sand alone. Both of these phenomena could give rise to further questions and investigations. Students could speculate on whether these problems would be reduced in space where there is less gravity (1.622 m/s² on the Moon, Earth 9.807 m/s², Mars 3.711 m/s²). An interesting fact based on problems of plant growth in reduced gravity is that when watered, plants get covered in a film of water, rather than the water draining off the leaves. This will affect light absorbance, gas exchange, and could trigger disease if microorganisms were present in the air. If microorganisms are found in space it is likely that they will have been introduced artificially by space explorers. Question and Answers Which soil provided the most favourable conditions for seed germination? Suggest a possible explanation. Possible answer: A mixture of sand and clay provides the best conditions. This may be due to better drainage and water retention, to different combinations of minerals present, or to temperature effects. Describe any differences you noted in the time taken for seeds to germinate in different soils. Possible answer: Seed germination times are different in different soils. In just clay or just sand, the seeds took longer to germinate. Which soil type promoted the fastest germination rates? Possible answer: Seeds germinate fastest in soils with mixed particle sizes. Soils on Mars have a particle size <1mm, whilst on the Moon particle size is <100μm. Explain the likely effect that these soils are likely to have on plant growth. Possible answer: From this investigation there is an optimum soil particle size. The Moon soil particles are very small and this investigation showed that seeds do not germinate easily on fine soils. Mars soil may be more successful for plant growth than Moon soil. Was there a difference in the percentage of seeds that germinated in different soil types? Possible answer: A greater proportion of seeds germinate in soils with mixed particle size. 11 Number of seeds germinated - Sample data Microgreen Broccoli Day 100% sand 75% sand 25% clay 0% clay Rocket 50% sand 50% clay 25% sand 75% clay 0% sand 100% sand 75% sand 100% clay 0% clay 25% clay 50% sand 50% clay 25% sand 0% sand 75% clay 100% clay 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 3 0 1 3 1 0 1 5 5 5 3 4 1 2 4 2 0 1 5 5 5 4 5 2 3 5 3 0 2 5 5 5 5 6 3 3 5 3 0 4 5 5 5 5 7 3 3 5 3 0 4 5 5 5 5 8 3 3 5 3 0 5 5 5 5 5 From this data students are recommended to make observations at two day intervals up to a maximum of ten days. If timetables do not allow this to happen, it may be possible for the seed trays to be photographed at two day intervals, and for students to analyse the photographs to collect their data. Suppliers Silver sand available from garden centres – about £5 – 5kg Modelling clay - craft shops – about £8 – 5kg Seeds – rocket and ‘windowsill microgreens’ eg broccoli and mixed salad leaves Information about exploring plant growth on Mars Short account of why scientists want to investigate plant growth on Mars, and the problems they are likely to encounter. http://www.smithsonianmag.com/smart-news/nasa-wants-build-greenhouse-mars-180951369/?no-ist Searching for signs of life on Mars – student resource and teachers guide on how to conduct soil tests and comparisons to model how soil samples from space are analysed. http://www.nationalstemcentre.org.uk/elibrary/resource/9916/searchingfor-signs-of-life-on-mars Is there anyone out there – soils. This is part of a series of lessons produced by ESERO for students aged 9-12 to model the activities of scientists involved in space exploration http://www.nationalstemcentre.org.uk/elibrary/resource/5689/is-thereanyone-out-there References ‘Can plants grow on Mars and the Moon: a Growth Experiment on Mars and Moon soil simulants’, G.W. Wieger Wamelink, PLOS One, August 27 2014. http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0103138 12 Student Worksheet / Name: Growing food for space exploration Instructions (see separate sheet for diagrams) You are going to mix sand and clay to make up a range of different soil samples. Each sample needs different proportions of sand and clay so that each soil has different proportions of large and small particles. You will then find out which soil type is best for germinating seeds. 1. Decide how many soil samples you will create by combining different proportions of sand and clay. 2. Decide how much soil you will need to fill each of the seed tray compartments. 3. Using a spoon, mix together different proportions of clay and sand to make your soil samples. 4.Put similar amounts of your different soil samples into compartments of a seed tray and label them. Press the soil down gently to firm it, and remove any air pockets. Each compartment should be filled to within 2cm of the top of the seed tray. 5. Label each soil mixture with information about the proportions of sand and clay used. 6. Pour water into each compartment and allow it to drain out into a tray so that each soil sample is completely wet. 7. Place the seed tray in a tray to catch any further water that drains out of the soil. 8. Place a number of seeds onto the soil surface, recording the number, plant type and soil type with the date. 9.Every few days count the number of seeds that germinate and record your findings. Look for the emergence of a shoot from the seed case. Once a shoot appears, then the seed has germinated. Record in a table the number of germinated seeds in each soil sample and the date of the recording. You can calculate the percentage germination in each soil sample by dividing the number of seeds that germinate by the number of seeds sown and multiplying this by 100. 13 Student Worksheet / Name: Growing food for space exploration Read these instructions carefully before you start. Mixture Powdered clay Seed tray Mixture Sand 1. Use a spoon to mix sand and powdered clay in different proportions. 2. Add different mixtures of sand and clay to each compartment of a seed tray. Seeds Tray Different mixtures of sand and clay 3. Water each compartment until water drains out of the bottom of the seed tray. 4. Place 5 seeds on the clay / sand mixture in each compartment. Label the compartments. Place on a tray and put to one side. 14 Student Worksheet / Name: For each soil sample you will need a table like the one below: Date No. seeds sown (b) No. seeds germinated (a) % germinated = (a/b) x 100 Note Ensure you wash your hands after handling soil and plant material. You need to cover any cuts with a plaster before handling soil. Avoid eating and drinking where there is a risk of contamination with soil borne microorganisms. Questions Describe any differences you noted in the time taken for seeds to germinate in different soils. Which soil type promoted the fastest germination rates? Was there a difference in the percentage of seeds that germinated in different soil types? Which soil provided the most favourable conditions for seed germination? Suggest a possible explanation. Soils on Mars have a particle size <1mm, whilst on the Moon particle size is <100μm. Explain the likely effect that these soils are likely to have on plant growth. 15 Nutritional Data Cards The cards provide basic information on 12 different plants that could be used to provide food and oxygen in future space missions The plants listed are spinach, carrot, radish, tomato, lettuce, spring onion, chilli pepper, strawberry, cabbage, basil, thyme, parsley Plants that are currently being considered for use in space by the European Space Agency (ESA) are soy bean, potato, soft white wheat, tomato, spinach, lettuce, beetroot, onion, rice (and spirulina – a photosynthetic cyanobacterium) The cards describe: Nutritional values – the percentage of human daily requirements each plant provides for vitamins A, C, B6 and for iron, calcium and magnesium Did you know? – historical, medical or other interesting facts Growing– how to grow from seed and the likely yield from each plant Information about how the plant is linked to space exploration The cards can be used for: Finding out which plants would provide the richest source of various nutrients Some of the reasons plants have been taken into space Planning a space garden, where soil, time and growing conditions are all limited European Space Agency space plants: Soy beans – a source of protein Onions – add flavour to space diets Potato, wheat and rice – source of carbohydrates for astronauts from different cultures Spirulina – a photosynthetic bacterium that recycles astronaut waste and can be eaten too Tomato, spinach, lettuce, beetroot – add colour and micronutrients to space diets 16 Spinach Carrot Spinacea oleracea Daucus carota Best For: Vitamin K Best For: Vitamin A Percent of your daily values in 1 cup Percent of your daily values in 1 cup Vitamin A: 56% Vitamin C: 14% Vitamin K: 181% Iron: 4% Calcium: 3% Magnesium: 6% Vitamin A: 367% Vitamin C: 10% Vitamin B6: 10% Iron: 1% Calcium: 3% Magnesium: 3% Space Connection: Space Connection: Students in Greece developed a solar-powered greenhouse to grow spinach on Mars called “Popeye on Mars”. The high carotenoid content of carrots provides valuable antioxidants to astronauts exposed to cosmic radiation on the ISS. History Conundrum: Super Healthy: In 1890, a researcher put the decimal point in the wrong place when calculating the iron content of spinach. Poor Popeye wasn’t getting nearly as much iron as he thought! A new variety of purple carrot provides increased anthocyanins, another type of antioxidant. A return to the roots of the originally purple carrots! Growing Spinach: Growing Carrot: Germination time: 16 days Yield per metre row: 1.0kg Growth time: 11 weeks Growth conditions: Needs rich soil and regular watering Germination time: 17 days Yield per metre row: 1.5kg Growth time: 16 weeks Growth conditions: Needs deep sandy soil Radish Tomato Raphanus sativus Solanum lycopersicum Best For: Vitamin C Best For: Vitamins A and C Percent of your daily values in 1 cup Percent of your daily values in 1 cup Vitamin A: 0% Vitamin C: 28% Vitamin B6: 5% Iron: 2% Calcium: 2% Magnesium: 3% Vitamin A: 29% Vitamin C: 41% Vitamin B6: 5% Iron: 5% Calcium: 1% Magnesium: 5% Space Connection: Space Connection: Radishes are used to study how exposure to microgravity and space environments might affect plant nutritional value and growth. An early NASA study investigated whether tomato seeds that had been in space would grow just as well on Earth. They did! Super Healthy: Did you know? Radishes are thought to have a cooling effect on the body. They are often used in alternative medicines to remove excess heat from the body during summer. Tomatoes contain large amounts of the antioxidant lycopene, which protects our skin from damaging UV rays. Eating more tomatoes might even make us look younger! Growing Radish: Growing Tomato: Germination time: 6 days Yield per metre row: 1.0kg Growth time: 5 weeks Growth conditions: Easy, and can be grown in small spaces Germination time: 16 days Yield per metre row: 3.5kg Growth time: 16 weeks Growth conditions: Needs considerable care and attention Lettuce Spring Onions Lactuca sativa Allium sp Best For: Vitamin A Best For: Vitamin K Percent of your daily values in 1 cup Percent of your daily values in 1 cup Vitamin A: 53% Vitamin C: 3% Vitamin B6: 0% Iron: 2% Calcium: 1% Magnesium: 1% Vitamin A: 19% Vitamin C: 31% Vitamin B6: 5% Iron: 8% Vitamin K: 259% Magnesium: 5% Space Connection: Space Connection: When NASA grew red romaine lettuce under red and blue light, it had much more anthocyanin – good for astronaut health! NASA is using spring onions to investigate whether plants grow better in monocultures, on their own, or with other plants as well. History Conundrum: Did you know? Romaine lettuce and other dark green leafy vegetables have high levels of antioxidants that can help reduce your risk for cancer. Another reason to eat your greens! One cup of spring onions provides 172% of your daily value of vitamin K. This vitamin is crucial for maintaining bone health and staving off Alzheimer’s disease. Growing Lettuce: Growing Spring Onions: Germination time: 9 days Yield per metre row: 3 lettuce heads Growth time: 11 weeks Growth conditions: Needs rich neutral or alkaline soil and regular watering Germination time: 21 days Yield per metre row: 1.0kg Growth time: 16 weeks Growth conditions: Easy to grow, can be planted in close set rows Chilli Pepper Strawberry Capsicum annuum Fragaria x ananassa Best For: Vitamin C Best For: Vitamin C Percent of your daily values in 1 cup Percent of your daily values in 1 cup Vitamin A: 24% Vitamin C: 606% Vitamin B6: 20% Iron: 12% Calcium: 0% Magnesium: 9% Vitamin A: 0% Vitamin C: 141% Vitamin B6: 5% Iron: 3% Calcium: 2% Magnesium: 4% Space Connection: Space Connection: There are plans to introduce chillies into astronauts’ diets, to increase interest and variation into their food. Strawberries smell just as nice in space as on Earth, providing a mental boost to astronauts. They also contain healthy antioxidants. Did you know? Did you know? Chillies contain capsaicin which stimulates pain receptors to give sensations of heat. Jalapeno chillies measure 5000 Scoville Heat Units, but some chillies are 2 million SHU. The strawberry variety used in gardens is a hybrid created by horticulturalists. The first hybrid was created in France in the 1700s, and we still use the same variety today! Growing Chilli Peppers: Growing Strawberry: Germination time: 17 days Yield per metre row: 8 fruits Growth time: 18 weeks Growth conditions: Difficult outdoors, needs regular watering and nutrients Germination time: Not easily grown from seed Yield per metre row: 0.5g Growth time: 20 weeks Growth conditions: Easy in well drained soil Cabbage Basil Brassica oleracea Ocimum basilicum Best For: Vitamins C and K Best For: Vitamin A and K Percent of your daily values in 1 cup Percent of your daily values in 1 cup Vitamin A: 1% Vitamin C: 54% Vitamin B6: 5% Iron: 2% Vitamin K: 85% Magnesium: 2% Vitamin A: 24% Vitamin C: 4% Vitamin B6: 0% Iron: 4% Vitamin K: 124% Magnesium: 4% Space Connection: Space Connection: Cabbage is prized by space nutritionists for its high content of vitamin K, for bone health, and dietary fibre, for healthy digestion. Basil seeds will be among the first seeds to grow on the moon in a “lunar greenhouse”, launching in late 2015. Did you know? Did you know? In ancient Rome and Greece, eating cabbage was thought to prevent drunkenness as they believed cabbage couldn’t grow next to grapevines. The strong scent of basil is caused by a variety of essential oils, with different proportions of the oils resulting in distinct aromas for different varieties. Growing Cabbage: Growing Basil: Germination time: 10 days Yield per metre row: 1.0kg Growth time: 30 weeks Growth conditions: Conditions: easy but need 40 cm between plants Germination time: 6 days Yield per metre row: 0.5kg Growth time: 16 weeks Growth conditions: Easy in warm well drained soil Thyme Parsley Thymus vulgaris Petroselinum crispum Best For: Vitamins A and C Best For: Vitamins A and C Percent of your daily values in 1 cup Percent of your daily values in 1 cup Vitamin A: 38% Vitamin C: 106% Vitamin B6: 6% Iron: 39% Calcium: 16% Magnesium: 16% Vitamin A: 101% Vitamin C: 133% Vitamin B6: 5% Iron: 20% Calcium: 8% Magnesium: 7% Space Connection: Space Connection: Thyme and other fresh herbs are highly valued by astronauts for their ability to add flavour to often uninspiring space meals. Parsley was one of the first plants grown in space by the Russian cosmonaut Valery Ryumin on the Salyut 6 space station. Did you know? Did you know? Thymol is a key component of thyme essential oil. It is an important antiseptic, originally used to medicate bandages. It may also be beneficial in preventing acne. Some varieties of parsley produce large root structures, which can be eaten much like carrots. Others are valued for their leafy stems with high antioxidant content. Growing Thyme: Growing Parsley: Germination time: 21 days Yield per metre row: 0.5kg Growth time: 15 weeks Growth conditions: Grows in poor soil, four plants per metre Germination time: 21 days Yield per metre row: 0.5kg Growth time: 10 weeks Growth conditions: Difficult to germinate but easy to grow Rocket Beetroot Eruca vescaria subsp sativa Beta vulagaris Best For: Vitamins A and K Best For: Iron Percent of your daily values in 1 cup Percent of your daily values in 1 cup Vitamin A: 47% Vitamin C: 25% Vitamin B6: 5% Iron: 8% Vitamin K: 28% Magnesium: 11% Vitamin A: 0% Vitamin C: 11% Vitamin B6: 5% Iron: 6% Calcium: 2% Magnesium: 7% Space Connection: Space Connection: There are a series of Rocket cultivars with a space connection in their name; Rocket ‘Adventurer’, ‘Discovery’, ‘Voyager’ & ‘Apollo’. European Space Agency scientists suggest beetroot as one of their top 10 crops to take on long term space missions. Did you know? Did you know? Rocket has been used in British salads since Elizabethan times, it has a peppery/ mustardy taste and is good to mix with other salad leaves. Beetroot is a versatile vegetable, the leaves are full of nutrients as well as the root, meaning the whole plant can be eaten. Growing Beetroot: Growing Rocket: Germination time: 5 days Yield per metre row: 350g Growth time: 5-8 weeks from sowing Growth conditions: Sow in well drained fertile soil, keep the soil shady and moist to avoid bolting (flowering early) Potato Solanum tuberosum Best For: Vitamin C Percent of your daily values in 1 cup Vitamin A: 0% Vitamin C: 32% Vitamin B6: 15% Iron: 4% Calcium: 1% Magnesium: 5% Space Connection: Five small potatoes were grown from tubers in the laboratory on board the space shuttle Columbia in 1995. Did you know? Potatoes originated in the Andes mountain range, South America. Over 200 species are found there in the wild. Growing Potato: Germination time: 2-3 weeks for first shoots to appear Yield per metre row: 3kg Growth time: 10-12 weeks to harvest Growth conditions: Chit (sprout) potatoes inside before planting outdoors Germination time: 15-21 days Yield per metre row: 1.5kg Growth time: 13-15 weeks Growth conditions: Sow in fertile well drained soil, keep watered every 10-24 days in hot weather Healthy eating for space travellers 17 Estimated time: One lesson Location: Laborato ry School term: All ye ar round Level of Experienc e: Good level of prac tical science experience require d Subject(s): Science Age group: 13-16 Healthy eating for space travellers Technical and Teaching Notes Outline Long-term space exploration will require astronauts to be provided with a varied diet for physical health and for psychological reasons. This student activity involves measuring the vitamin C content of a range of vegetables and developing a number of technical and investigative skills. Further activities are suggested including assessing the impact of cooking on the nutritional value of food and research into VEGGIE and MELiSSA projects. Interpret data. Explain features of a healthy diet. Learning outcomes Handle equipment and chemicals safely and with precision. Apparatus – vitamin C content investigation For each small group of 2-3 students: 50cm3 0.1% dichlorophenolindophenol (DCPIP). Weigh out approximately 0.24 g DCPIP (Mr¬ = 268.1g/mol) and make up to 1 L with distilled water. A range of fresh vegetable leaves such as spinach, basil, parsley and lettuce. Each group requires 1.0g of leafy material from each plant. Pestle and mortar DCPIP solution is blue, but is decolourised by ascorbic acid although a faint pink colour may remain in acid solutions. DCPIP needs to be freshly prepared. Scissors 10cm3 measuring cylinder 200mg vitamin C tablet or ascorbic acid. This is for the preparation of a standard solution, so colourings and flavourings to be avoided if possible. Filter funnel, filter paper, small beaker Test tubes in rack, pen to label tubes Graph paper Disposable 2cm3 graduated plastic pipettes, or disposable 1cm3 syringe A top-pan balance (1 d.p.) for students to weigh their vegetable samples. 18 Safety Notes Students need to be warned of the hazards associated with handling plant material (allergies). Eye protection is required when using pestle and mortar and handling chemicals. Introduction and context Dietary supplements such as vitamin C (ascorbic acid) will be needed if humans are to spend extended periods of time exploiting space. Some vitamins are damaged by dehydration and storage, so a supply of fresh vegetables will be needed to supply the nutrients needed to keep space travellers healthy. (It is thought ‘vitamin’ is derived from ‘vital amine’ – a group of compounds that must be included in a human diet) Vitamin C can be obtained from meat and from plants. It is made by plants to protect them from oxidation damage during photosynthesis. The vitamin C content of foods deteriorates with time, particularly if food is not kept cool in a dry atmosphere. This is why growing fresh vegetables in space provides a better supply of vitamin C than transporting food from Earth. Vitamin C plays a vital role in protecting against scurvy. It is a cofactor in several enzyme reactions and is an antioxidant in humans. In plants it is associated with cell division and cell wall formation. This need has given rise to a number of NASA experiments on growing plants in space including the development of growth chambers on ISS and a planned experiment on Mars. But which plants should be grown to provide a vitamin C supplement to the space diet? The following investigation is used to compare the vitamin C content of different plant material. The investigation may be supplemented with the nutrition data card resource that provides information about the food content of different plants. The cards also show a number of other nutrients essential for human health. Many animals can produce their own vitamin C from glucose, but others have lost the ability to make the enzyme responsible for vitamin C manufacture. Animals that cannot make vitamin C include guinea pigs, many bats, some birds and apes, including humans. These animals need to include vitamin C in their diet to stay healthy. In humans the main function of vitamin C is to support a number of enzyme reactions, including those that build collagen. This is a protein that plays an essential part in providing the structure of connective tissue and skin. Without sufficient vitamin C in the diet, humans are likely to show symptoms of scurvy, a disease affecting skin and gums, and which was a major problem for sailors in previous centuries. At one time British sailors were provided with citrus fruit in their diet to prevent scurvy, giving rise to the nickname ‘limeys’. In this investigation students measure the vitamin C content of different plant material using a simplified titration technique with DCPIP. Suggestions are included for carrying out serial dilutions to produce a calibration chart. The activity provides opportunities for the development of mathematical skills such as unit conversion and expressing numbers in standard form. 19 Teaching Notes The activity can be simplified for students by providing them with calibration curve data. The activity could be further simplified by using initial results data of the volume of DCPIP used as a semi quantitative comparison of the different vegetable extracts, without conversion to vitamin C equivalents. DCPIP (2,6-dichlorophenolindophenol) reacts in 1:1 ratio with ascorbic acid (vitamin C) causing the indicator to become colourless. The procedure has been modified in this investigation by substituting dropping pipettes for titration apparatus and burettes for reasons of manageability and economy. If preferred, 1cm3 syringes rather than dropping pipettes may be used to simplify measurement of the volume of DCPIP added. The investigation provides an opportunity for practising serial dilutions, conversion of units and standard form, and for introducing calibration curves. DCPIP solution should be freshly made. In this investigation the concentrations used should require about 1cm3 DCPIP solution to produce a lasting blue solution when mixed with 1cm3 of vegetable extract for vegetables rich in vitamin C. DCPIP is considered low hazard. The student sheet provides details of the procedure for ‘titrating’ the vitamin C in a vegetable extract with DCPIP, for producing a serial dilution of a standardised vitamin C solution and using this to produce a calibration curve. Finally students convert their vegetable extract titration data into concentration of vitamin C using the calibration curve. A number of different plants have been used in previous space missions to explore ways of providing food, or recycling human waste. Such space projects include ‘VEGGIE’ and ‘MELiSSA’. Students interested in plants grown for food in space could research either of these two projects using references provided towards the end of this document. Veggie plant growth facility. Photo credit NASA 20 Answers to questions on student sheets Provide evidence to support your recommendation for which vegetables should be grown in space and used as sources of vitamin C. (Hint: refer to the nutrition data cards provided for this project) Possible answer: Answers should include data from either their investigation or from the nutrition data cards as evidence to support their recommendations. What vital role does vitamin C play in human metabolism? Many fruits are a good source of vitamin C. Discuss why it may be preferable to grow vegetables rather than fruits in space to provide vitamin C for space travellers. Possible answers: It supports enzyme reactions in a variety of different activities of the cell, including the formation of collagen, a protein essential for the formation of connective tissue. Possible answer: Fruits only develop after pollination on many plants. In space there would be no pollinating insects, and so pollination would need to be done artificially, increasing the demands made on space explorers to grow food. Fruits also take longer to develop than many vegetables, particularly leafy vegetables. What sources of vitamin C were provided for maritime travellers in previous centuries? Possible answers: James Lind in 1753 recommended citrus fruit as a cure and prevention for scurvy. The British Navy took up his suggestion several decades later. Captain Cook was said to have avoided scurvy amongst his crew when exploring the Pacific by insisting on fresh vegetables when possible and providing sauerkraut. An outline of the procedure is available from SAPS: http:// www.saps.org.uk/secondary/teaching-resources/191 What symptoms are associated with vitamin C deficiency? Possible answers: Lethargy, skin deterioration, gum disease and jaundice, scurvy. Suppliers Vegetables – available from greengrocers and supermarkets. References The VEGGIE project – an outline of the project to grow food in space including images from ISS http://www.nasa.gov/ content/veggie-plant-growth-system-activated-on-international-space-station/ - .VQF0kULv2fQ The MELiSSA project to recycle human waste in space – project outline and images http://www.esa.int/Our_Activities/ Space_Engineering_Technology/MELiSSA_life_support_project_an_innovation_network_in_support_to_space_exploration Further information Food for space flight. This article gives a brief history of food from the earlier missions and goes on to describe food preparation and menus used today http://www.nasa.gov/audience/forstudents/postsecondary/features/F_Food_for_Space_Flight.htm Food in space. This video explains the criteria used in selecting appropriate foods for space travel and includes an activity on foods and storage for 11-13 year old students. http://www.nationalstemcentre.org.uk/elibrary/resource/1126/food-in-space (Suitable 11-12 year olds) 21 Student Worksheet / Name: Healthy eating for space travellers Instructions (see separate sheet for diagrams) 1. Crush 2.0g of green leaves from a vegetable with 10.0cm3 water using a pestle and mortar. Filter your mixture to produce a clear (but coloured) solution. 2.Take 1.0cm3 of your solution in a test tube. Use a disposable pipette to add a single drop of indicator (DCPIP) at a time. Mix the solutions and keep adding indicator until the blue colour of the indicator does not disappear. 3. Record the number of drops of indicator needed to produce a permanent blue coloured solution. 4.Repeat this with other vegetables, making sure you are careful to measure and record the quantities accurately. Making a calibration chart 1. Dissolve a 200mg vitamin C tablet in 10.0cm3 water. Label the tube with the concentration of vitamin C. 2.Measure out 5.0cm3 of your vitamin C solution into a clean tube and mix with 5cm3 of water. Label this tube with the concentration of vitamin C. 3.Measure out 5.0cm3 of the second (diluted) solution and mix with 5.0cm3 water. Label this third tube with the concentration of vitamin C. 4.Repeat this process until you have made up a range of vitamin C solutions of different concentrations. 5.Measure how much indicator is needed to make 1.0cm3 of each of your dilutions produce a permanent blue coloured solution using the technique used with your vegetable solution samples. 6. Draw a graph of your results – concentration of vitamin C against number of drops of DCPIP indicator. 22 Student Worksheet / Name: Healthy eating for space travellers Read these instructions carefully before you start. Add 10cm3 water Filter paper Pestle Funnel 2.0g of plant material Boiling tube in rack 2. Filter the mixture to produce a clear solution. 1. Crush 2.0g of plant material with 10cm3 water. Pipette containing DCPIP solution 1.0cm3 of clear solution 3. Add one drop at a time until the solution stays blue. Record how many drops are required to produce a permanent blue solution 23 Student Worksheet / Name: Converting amount of indicator into vitamin C concentration in vegetables. 1.Use the chart to convert the number of drops of indicator used for each vegetable into the amount of vitamin C contained in each sample of vegetable extract. Recommend which vegetables should be considered for use as a source of vitamin C for space travellers. Use the nutrition data cards to compare your results with standard values, and find out what other information needs to be considered when deciding on suitable candidates for ‘space food’. 2.Present your results as a comparison of the amount of vitamin C found in different vegetables. Note Ensure you wash your hands after handling plant material and chemicals. Wear eye protection when handling chemicals and when using a pestle and mortar. Questions Provide evidence to support your recommendation for which vegetables should be grown in space and used as sources of vitamin C. (Hint: refer to the nutrition data cards provided for this project) Many fruits are a good source of vitamin C. Discuss why it may be preferable to grow vegetables rather than fruits in space to provide vitamin C for space travellers. What symptoms are associated with vitamin C deficiency? What vital role does vitamin C play in human metabolism? What sources of vitamin C were provided for maritime travellers in previous centuries? 24 Hazards of space travel 25 Estimated time: On e lesson Location: Classroo m or Laboratory School term: All ye ar round Level of Experienc e: KS3, S1-2 & KS4, S3 -4 Subject(s): Science Age group: 13-16 Hazards of space travel: Modelling mutation in seeds with Rabidops Technical and Teaching Notes Outline There is an increased risk of mutation by ionising radiation in space due to the absence of the Earth’s magnetic field. An activity is provided to explore the effect of deletion mutations on chromosomes and on subsequent development of an imaginary organism – Rabidops. Two versions of the activity have been provided. The simplified version has six chromosomes and two pairs of alleles (labelled ‘2 genes version’); the more complex version has ten chromosomes and six pairs of alleles. Each version uses a different decoding sheet. Present reasoned explanations, including explaining data in relation to predictions and hypotheses. Explain that genetic variation arises through mutation. Learning outcomes I nterpret observations and data, to draw conclusions. Two model Rabidops plants showing variation in leaf colour and shape, stem length and number and flower colour and number. Photograph of Arabidopsis (thale cress) used extensively in genetics research and also used to investigate the effects of reduced gravity on plant growth in space. 26 Apparatus for Rabidops activity For each group of students: If using the simplified version for each group of students: Set of 10 chromosomes 10 paper clips Large marshmallow (to represent growth medium) Midget gem sweets in assorted shapes and colours (to represent leaves) Jelly Tots sweets in assorted colours (to represent flowers) Cocktail sticks, 5 or 6 (to represent stems and leaf stalks) Decoding sheet Set of 6 chromosomes 5 paper clips Large marshmallow (to represent growth medium) Midget gem sweets in assorted shapes and colours (to represent leaves) Jelly Tots sweets in assorted colours (to represent flowers) Cocktail sticks, 3 or 4 (to represent stem and leaf stalks) Simplified decoding sheet Print the chromosomes onto card, and cut out the individual chromosomes. Laminating the card with plastic will allow them to be reused by other classes. Fasten a set of ten chromosome strips together with a paper clip. If you are using the simplified version, use the alternative template with six chromosomes. Introduction and context: cause changes in the organism. The mutation will also be passed on to future generations of plants. The risks of mutation can be reduced by using heavy shielding, both in space vehicles and in greenhouses used to grow crops on Mars and the Moon. This adds to the cost of growing food in space, as the shielding is heavy, requiring extra fuel for transport. Prepare for this lesson by explaining that your course requires students to know about the structure and function of DNA, what genes are and the fact that chromosomes exist in homologous pairs. Rabidops are imaginary plants made from midget gem sweets and cocktail sticks. Their features are determined by genes contained within their chromosomes. One of the hazards of space travel is increased risk from solar and cosmic radiation. Solar energetic particles (SEPs) and galactic cosmic rays (GCRs) can severely damage genetic material by deleting sections of DNA in the chromosome. Once such a deletion mutation occurs, the gene is no longer able to produce normal protein from that gene which can Mutations happen spontaneously and at random, but the risk of deletion mutation increases significantly once outside the Earth’s protective magnetic field. The consequences of such mutations depend on which part of the chromosome is affected, and whether the gene on a homologous (paired) chromosome is also affected. In this activity students should learn that: Features of plants (their phenotype) are determined by paired genetic material on homologous chromosomes. Certain types of mutation such as deletion mutation are spontaneous and occur at random positions on chromosomes. The risk of deletion mutation increases when living material is transported through space unless expensive shielding can be provided. Safety Note: Make sure students don’t eat the marshmallows or sweets if you are working in a laboratory. 27 ? Teaching Notes Purpose To model the effects of radiation in space on plant growth. To explain the effects of mutation on chromosomes. To show that mutation is a naturally occurring random process. places like Mars and the Moon. Provide students working in groups with the relevant student procedure sheet, set of chromosomes, a number of paper clips to represent damaged DNA, and decoding sheet plus the materials to build their Rabidops plant. Rabidops are loosely based on Arabidopsis, a plant used extensively in genetics research and also used in several space experiments looking at the effect of gravity on plant growth. In this activity you can investigate the effect of different levels of radiation on gene mutation. The model assumes that all radiation hitting the chromosome will cause a mutation, but in living systems, some radiation can pass through the cell nucleus without causing damage. Students place their paper chromosome set face down and randomly distribute. They then model the effect of different levels of radiation on the genetic material of the plant. This involves placing paper clips at random positions on the chromosomes. Low levels of radiation are represented by five paper clips, moderate radiation by eight paper clips and high levels by ten paper clips. This makes the point that mutation occurs spontaneously even when there are low levels of ionizing radiation. It should be pointed out that this is a ‘worst case’ model and that not all radiation passing through a nucleus will necessarily cause mutations. Explanation of Rabidops for students: Rabidops are imaginary plants that have been used in space to investigate the effect of radiation. Imagined Rabidops have a typical appearance of round green leaves and multiple long stems with a number of red flowers on each stem, called ‘wild type’. You can model Rabidops plants’ using cocktail sticks and sweets to show how the genes in the chromosomes of the plant exert control over the plants appearance. In this model you will be given paper strips representing all of the ten chromosomes to be found in a single embryo cell inside a Rabidops seed. Your task is to establish the effect of mutations on the chromosomes and to make a model of the plant to show its appearance if it was to grow from the mutated seed. The chromosomes are then turned face up and arranged in homologous pairs. If a paperclip partially or wholly covers a specific gene, that gene is considered ‘mutated’ and therefore destroyed. The results are analysed on a decoder sheet so that the effect on the appearance of the Rabidops plant can be established. Explain that the students will be working in groups to investigate the effect of ionizing radiation on genes. The genes are located within the chromosomes of embryo cells of seeds transported through space for growing crops. The crops could provide food in space stations such as the International Space Station (ISS) or to support humans when exploring The exercise models mutation, and shows that if a mutation occurs on a chromosome, it may not damage the genes that code for phenotype characteristics. If such a gene is damaged, the presence of a similar gene on a homologous chromosome may result in no change in the phenotype of the organism. 28 Answers to questions (both versions) 1. Consider each of the characteristics in turn. Which, if any, of the mutated form of the characteristics could be harmful to the plant? Possible answer: Leaf colour – pale leaves could be due to less chlorophyll being made which would limit the rate of photosynthesis. Flower number – a reduced number of flowers would reduce the amount of fruit and seed made by full plant Leaf shape – a reduction in leaf area would reduce the rate of photosynthesis. Very elongated leaves may be more susceptible to wind damage. Flower colour – if the flower is insect pollinated this would affect the chance of the flower being detected by insects. In space this is unlikely to be a problem as there are no insects and all insect pollinated plants would need to be artificially pollinated if they are to set seed. Stem length – shorter stems reduce the chance of pollination and could limit seed dispersal. Stem number – fewer stems would reduce the number of flowers, and so reduce the number of fruits and seeds made by the plant. 2. Assess the likely impact on the plant of low level radiation using the findings from your model. How much does the risk to the plant change when radiation is at moderate or high level? You may need to compare your findings with those of other groups before answering this question. Possible answer: At low levels of radiation there is a small chance of a mutation happening. Many mutations do not affect the genes that determine characteristics and both copies of the gene need to be mutated to affect the appearance of the plant. Therefore at low levels of radiation the chances of a mutation affecting the appearance of the plant are small. When the radiation dose increases and the chances of a mutation happening are higher, the mutation is more likely to affect genes that determine appearance, and there is a higher chance of the mutation affecting both copies of the gene. At high levels of radiation, the effect on the plant is likely to be significant. The model does not take account of repair mechanisms in the cell that can replace damaged portions of chromosomes. 3. What advice would you have for anyone intending to set up a crop growing facility on another planet based on your findings? Possible answer: It is important to protect crops against the effects of radiation both in transport to the planet and whilst growing on the planet surface. Transparent shielding would be vital. Sample data ‘Low level of radiation’ – 5 paper clips used - bold text indicates result obtained Characteristic No mutation Single mutation Double mutation Leaf colour Lc / Lc / Green Lc / — / Green -- / -- / Pale Leaf shape Ls / Ls / Round Ls / — / Round -- / -- / Oval Stem length SL / SL / Long SL / — / Long -- / -- / Short Stem number Sn / Sn / Multiple Lc / — / Multiple -- / -- / Single Flower number Fn / Fn / Multiple Lc / — / Multiple -- / -- / Single Flower colour Fc / Fc / Red Lc / — / Pink -- / -- / White Outcome – wild type leaf colour, leaf shape, stem length, flower number and flower colour but only single stem. 29 Sample data ‘High level of radiation’ – 10 paper clips used – bold text indicates result obtained Characteristic No mutation Single mutation Double mutation Leaf colour Lc / Lc / Green Lc / — / Green -- / -- / Pale Leaf shape Ls / Ls / Round Ls / — / Round -- / -- / Oval Stem length SL / SL / Long SL / — / Long -- / -- / Short Stem number Sn / Sn / Multiple Lc / — / Multiple -- / -- / Single Flower number Fn / Fn / Multiple Lc / — / Multiple -- / -- / Single Flower colour Fc / Fc / Red Lc / — / Pink -- / -- / White Outcome – wild type leaf colour, stem length, flower number, but oval leaf, single stem and pink flower. ‘Simplified version’ – 5 paper clips used Characteristic No mutation Single mutation Double mutation Leaf colour Lc / Lc / Green Lc / — / Green -- / -- / Pale Flower colour Fc / Fc / Red Lc / — / Pink -- / -- / White Outcome – wild type leaf colour, stem length, flower number, but oval leaf, single stem and pink flower. Note: The model could be extended by looking at the impact of interbreeding between the resulting plants, and the likely effect this would have on future generations of crops, to demonstrate dominance and absence of dominance, both with further radiation damage, or with low levels of mutation. Suppliers: The resources for making Rabidops are available from supermarkets or local shops Acknowledgements: The idea for the Rabidops activity was developed from the use of ‘Reebops’ for teaching inheritance. Details of the Reebops modelling activity are available on the practical biology site www.nuffieldfoundation.org/practical-biology/making-reebops-model-meiosi Thanks to Science and Plants for Schools (SAPS) for producing these resources’ 30 Student Worksheet / Name: Hazards of space travel: Modelling Rabidops Mutation 1. Decide on the level of radiation that the chromosomes will experience (low, moderate or high). 2.Place your six chromosomes face down and randomly arranged. ollect the required number of paper C clips to represent damaged sections of chromosomes. 3. Attach all of the clips to the chromosomes – in random positions to simulate the effect of radiation hitting the chromosomes. o not look to see if your paper clips D have covered any of the named genes at this stage. low radiation level – 5 clips; moderate radiation level – 8 clips; high radiation level – 10 clips 4. Turn over the chromosomes so that you can now see the named genes. Match up the pairs of chromosomes. 5. Use the decoding sheet to translate the genetic information into information about the appearance of the plant. Identify which genes have a paper clip attached to them – either wholly in the gene or overlapping the edge of the gene. These will be the genes damaged by mutation. Draw a circle round the gene combination for each feature (both normal; one normal/ one damaged; both damaged). 6.Collect the materials needed for making your model. Using the information on the decoding sheet, construct a model Rabidops plant to show the appearance of the leaves and flowers. Compare your model with the models made by other groups, noting the levels of radiation used in each case. Questions 1. C onsider the leaf colour and the flower colour of the plant. How harmful would it be to the plant if either of these characteristics were mutated? 2. I n your modelling activity can you explain why not all the mutations caused a change in the plant’s appearance? 3. What advice would you have for anyone intending to set up a crop growing facility on another planet based on your findings? Safety Note: Do not eat the component parts of the Rabidops models. 31 Student Worksheet / Name: Resources 1a Hazards of space travel: Modelling mutation in seeds with Rabidops Decoding Sheet: The genes studied are... Gene Name Characteristic Appearance Lc Ls SL Sn Fn Fc Leaf colour Leaf shape Stem length Stem number Flower number Flower colour Wild type: green Wild type: round Wild type: long Wild type: multiple Wild type: multiple Wild type: red Mutation: pale Mutation: oval Mutation: short Mutation: single Mutation: single Single mutation: pink Double mutation: white Circle the combination of genes to find out the appearance of your Rabidops plant. If a gene has a paper clip fully or partially covering it, then it should be ignored as the gene has been deleted (mutated). Characteristic No mutation Single mutation Double mutation Leaf colour Lc / Lc / Green Lc / — / Green -- / -- / Pale Leaf shape Ls / Ls / Round Ls / — / Round -- / -- / Oval Stem length SL / SL / Long SL / — / Long -- / -- / Short Stem number Sn / Sn / Multiple Sn / — / Multiple -- / -- / Single Flower number Fn / Fn / Multiple Fn / — / Multiple -- / -- / Single Flower colour Fc / Fc / Red Fc / — / Pink -- / -- / White 32 Student Worksheet / Name: Resources 2a Print this sheet and cut columns into strips to model chromosomes SL SL Sn Lc Lc Sn Ls Ls Fn Fn Fc Key Lc Ls SL Sn Fn Fc Leaf colour Leaf shape Stem length Stem number Flower number Flower colour 33 Green/Yellow Long/Round Long/Short Multiple/Single Multiple/Single Red/Pink/White Fc Student Worksheet / Name: Hazards of space travel: Modelling Mutation (2 genes version) 1.Your chromosome set is going to be exposed to radiation levels higher than on Earth. 2.Place your six chromosomes face down and randomly arranged. The radiation that affects the chromosomes causing mutation is represented by five paper clips. 3. Attach all of the clips to the chromosomes – in random positions to simulate the effect of radiation hitting the chromosomes. o not look to see if your paper clips D have covered any of the named genes at this stage. 4.Turn over the chromosomes so that you can now see the named genes. Match up the pairs of chromosomes. 5. Use the decoding sheet to translate the genetic information into information about the appearance of the plant. Identify which genes have a paper clip attached to them – either wholly in the gene or overlapping the edge of the gene. These will be the genes damaged by mutation. Draw a circle round the gene combination for each feature (both normal; one normal/ one damaged; both damaged). 6.Collect the materials needed for making your model. Using the information on the decoding sheet, construct a model Rabidops plant to show the appearance of the leaves and flowers. Compare your model with the models made by other groups, noting the levels of radiation used in each case. Questions 1. Consider the leaf colour and the flower colour of the plant. How harmful would it be to the plant if either of these characteristics were mutated? 2. I n your modelling activity can you explain why not all the mutations caused a change in the plant’s appearance? 3. What advice would you have for anyone intending to set up a crop growing facility on another planet based on your findings? Safety Note: Do not eat the component parts of the Rabidops models. 34 Student Worksheet / Name: Resources 1b Hazards of space travel: Modelling mutation in seeds with Rabidops Decoding Sheet (2 genes version): The genes studied are... Gene Name Characteristic Appearance Lc Fc Leaf colour Flower colour Wild type: green Wild type: red Mutation: pale Single mutation: pink Double mutation: white Circle the combination of genes to find out the appearance of your Rabidops plant. If a gene has a paper clip fully or partially covering it, then it should be ignored as the gene has been deleted (mutated). Characteristic No mutation Single mutation Double mutation Leaf colour Lc / Lc / Green Lc / — / Green -- / -- / Pale Flower colour Fc / Fc / Red Fc / — / Pink -- / -- / White 35 Student Worksheet / Name: Resources 2b 2 genes version – 2 genes and three chromosomes Print this sheet and cut columns into strips to model chromosomes Lc Lc Fc Fc Key Lc Fc Leaf colour Flower colour RHS Registered Charity No. 222879/SC038262 36 Green/Yellow Red/Pink/White