Duncanrig Secondary School S3 Biology Course Commercial Use of Plants Pupils Activity Booklet
What you should know by the end of this unit: Plants provide food - e.g. wheat for making bread. Plants provide medicines - e.g. foxgloves are used to produce a medicine used to treat an irregular heartbeat. Plants provide raw materials - e.g. timber for building materials. Due to an increasing world population there is an increasing demand for commercially grown plants. Biofuels are fuels produced from plants. Biofuels are a renewable source of energy. Examples of plants grown to produce biofuels. Advantages and disadvantages of growing plants commercially to produce biofuels. The yields of crops can be increased by applying fertilisers and pesticides. The yields of crops can be increased by genetically modifying plants. Genetic modification involves transfer of genetic information from one species to another. Plants can be genetically modified to 1. Give them resistance to diseases. 2. Enable them produce chemicals which protect them from harm from insects or herbicides. 3. Make them healthier to eat. 4. Enable them to produce pharmaceuticals. The benefits and risks of GM plants. 2
Skills that you should be able to carry out by the end of this unit are: Research the commercial uses of plants and present this information as a fact sheet. Working with a partner or group, through research and discussion, consider some of the advantages, disadvantages and ethical issues arising from plants produced commercially for biofuels. With a partner or in a group, through discussion, give a reasoned argument for or against the use of genetically modified (GM) plants. Work as part of a group and take responsibility to support the work of the group. 3
Plants are extremely important to the lives of people throughout the world. In addition to adding oxygen to the atmosphere and removing carbon dioxide (the gas that contributes to global warming) they are used by man to provide basic living needs. These uses can be split into 3 broad categories Food Medicines Raw Materials These needs are growing rapidly because of a growing world population and increasing incomes in developing economies such as India and China and urbanisation. While some of the worlds population rely on subsidence farming to satisfy their basic needs, the majority rely on crops grown on a large commercial scale for profit. Plants for Food Production Plants provide food for humans and also food for livestock which humans then eat. Millions of people around the world can be sustained on plants producing cereals. This is the reason w hy w heat is the most important food in the western world, corn in many parts of America and rice in Asia. Plants also provide us with fruit and vegetables which supply us with vitamins and minerals necessary for a healthy diet. Many well known drinks such coffee (which is made from the seeds of the coffee plant) and tea (which is made from the leaves of the tea plant) are commercially important crops. wheat is used to make bread 4
Plants for Medicines The healing properties of plants have been used since ancient times to cure disease. Foxgloves contain a substance called digitoxin which is used to treat an irregular heartbeat. Compounds from daffodil bulbs are being used to treat Alzheimer's disease and opium compounds from the opium poppy are used to make powerful painkillers. foxglove opium poppy Plants for Raw Materials Many raw materials are derived from plants. Timber from trees is used for furniture and for roof beams, doors and skirting in the construction industry; wood pulp is used in paper making; cotton from the cotton plant and linen from the flax plant are used to make fabrics, while wood and coal are used for fuels. Components such as rubber from the sap of the rubber tree, oil for lubricants and tannins to colour leather are all obtained from plants for industrial use. Soaps, perfumes and essential oils from a variety of plants are used for the cosmetics industry. cotton plant timber production 5
Activity 1 : Construct a table like the one below. Using the information from the previous pages, summarise the commercial uses of Category Plant Source Commercial Use 1. 2. 3. 1. 2. 3. 1. 2. 3. 1. 2. 3. 1. 2. 3. 1. 2. 3. Scots Pine: Fact sheet Scots pine is the only native conifer grown commercially for timber. It can grow up to 36 metres tall and 1.5 metres around the trunk. The leaves are long needles that grow in pairs. The seeds are protected inside cones. It is used in many parts of the home including roof timbers, stairs, door ways and furniture. Its pleasant smell makes it an attractive firewood. In the past it was used to make ships, ships masts and water wheels. The resin from the tree was used to make tar and turpentine. Activity 2 : Using the class resources choose another tree species which is grown in the UK and research its commercial uses. Create a fact sheet showing the following information. The name of the tree species. Physical features of the tree. Where and how the tree grows. Present commercial uses. Past commercial uses. 6 6
Producing Plants for Fuels. Presently most of the worlds energy comes from fossil fuels; coal, oil and gas. These energy sources are nonrenewable which means that once they have been used they cannot be replaced. With the current rise in petrol prices, the threat of global warming and the worry that fossil fuels will run out, the use of plants for the production of biofuels has attracted increasing attention. The advantage of biofuels is that they are renewable meaning that the plant material from which they are made can be replenished. Most of the biofuels currently used come from crops grown by farmers. Oils can be extracted from soyabean, oilseed rape, sunflowers Sugar cane Corn Wheat New types of biofuels made from algae or nonfood crops are being developed but commercial production is still some years away.? Key Questions (Answer in sentences) 1. What are biofuels? 2. Explain why biofuels are now being considered as an alternative source of energy to fossil fuels. 3. What is the advantage of using biofuels as a source of energy compared to fossil fuels? 4. Give two named examples of plants grown for biofuel production. 5. 7
Activity 3 : Working in groups, consider some of the advantages and disadvantages of growing plants to produce biofuels. 1. Collect a set of Biofuel Fact Sheets from your teacher. 2. Read each fact sheet carefully. 3. Summarise the main points from each Biofuel Fact Sheet. You should consider the following: What is it made from? Where is the biofuel used? How does it work? What are the advantages of using this particular biofuel? E.g. to the environment, people, wildlife, money. What are the disadvantages of using this biofuel? 4. Looking at each Biofuel in turn, as a group, consider which one you think is the best option and why. 5. As a group you must prepare a sales pitch which you will present to the class on why your chosen fuel is the best option for commercial production. 8
Biofuels: ethical issues As we have learned, fossil fuels contribute to global warming, supplies are dwindling and more eco-friendly alternatives are required. However, biofuels may not be the best option if their production harms the environment, causes pollution and damages human health. It is important that such factors are considered by society and policy makers when evaluating alternative energy sources. Activity 4 : Working w ith a partner, consider the affected parties and competing interests in the production of biofuels. 1. Collect a set of Diamond Rank Biofuel Cards from your teacher. 2. Read all the cards carefully. In discussion with your partner, rank each card in order of priority starting from highest at the top, followed by two in second place, three in third place, a further two and then a card which represents the lowest priority at the bottom. You will have to decide which cards to discard. 3. Once you have sorted out your cards you will get a chance to discuss your choices with the rest of the class. 1 2 3 4 5 6. 7 8 9 9
Improving Yields Applying chemicals to plants can increase crop yields. Fertilisers make crops grow faster and bigger so that crop yields are increased. These contain minerals such as nitrogen, potassium and phosphorus, which help plants to grow. Pesticides are a special kind of chemicals for crop protection. These products protect plants from damaging influences such as weeds, diseases or insects. Pesticides include: herbicides which kill or stop weeds growing, insecticides which protect against insects and fungicides which stop or prevent invasion by harmful fungal diseases. Crop facts Crop protection products combat global malnutrition and starvation by increasing crop yields, helping families worldwide afford more fresh produce. Crop facts Although the world population has doubled in the last 40 years, the area of land devoted to food production has remained virtually constant; crop protection products have enabled farmers to produce higher yields of their crops on less land. In fact, U.S. farmers provide 18% of the world s food supply on only 10% of the world s farmland. Crop facts Organic farmers use pesticides, too. They apply non-synthetic crop protection products, such as sulphur and copper, to protect crops from pests and increase yields. Crop facts The Irish potato famine was caused by a fungus that still exists today, but its spread is alleviated through the use of fungicides.? Key Questions (Answer in sentences) 1. Name two types of chemical that are applied to crops to increase yields and explain how they do this. 2. How does mankind benefit from increased crop yields? 3. How do organic farmers protect their crops? 10
Improving Plants The world s plants are capable of producing an enormous variety of substances. With genetic engineering the potential exists to modify plants. New traits can be introduced that can make plants healthier for humans to eat or to improve crop yields by introducing resistance to disease. Traits can also be introduced that enable them produce chemicals which protect them from harm from insects or herbicides. GM crops are not only produced for human consumption some are genetically modified so that they can produce valuable pharmaceuticals (called pharming), fuels, biodegradable materials for industry or enzymes that can improve animal feed. Genetically Modified plants Bananas developed for vaccine production Drought resistant sugar cane Crops of maize resistant to pests How does the process work? The first step in genetic modification is to identify a gene for a particular characteristic. The gene, which may come from any organism, is inserted into the DNA of a plant cell, giving it the same trait. Once the new gene has been introduced the plant can be bred to create a new strain that passes the trait from generation to generation. 11
The Debate over Genetically Modified Crops Consider the following situations. What would you do? You are the leader of a developing nation. Hunger is a problem among citizens of your country: the saline (salty) coastal wetlands of your country can't support the growth of needed crops, and your poor economy can't support importing enough food for everyone. A biotechnology company has genetically modified a rice plant that can thrive in salt water, providing your nation with the opportunity to feed its citizens while bolstering its economy. You are a tomato farmer whose crops are threatened by a persistent species of beetle. Each year, you spend large sums of money for pesticides to protect your crops. A biotechnology company introduces a new strain of tomato plant that produces a natural pesticide, making it resistant to the beetle. By switching to this new strain, you could avoid both the beetle and the chemical pesticides traditionally needed to fight it. As a family physician, you often treat children who suffer from infectious diseases that could easily be prevented through vaccination. But the parents of many of your patients cannot afford the cost of vaccinations. You hear of a new approach that would reduce the cost to a fraction of its current price: genetically modified fruits and vegetables that contain various vaccines. By simply eating a banana, a child could be protected against disease - without getting a shot! Man s ability to manipulate plants by introducing new genes promises innovative solutions to these and many other real-world problems. Yet there is considerable opposition to the use of genetically modified plants for food production and other uses. Activity 5 : Working w ith a partner, you w ill consider the benefits and risks of genetically modified (GM) plants. 1. Collect a set of GM Sort Cards and a GM Plants Summary Sheet for you and your partner from your teacher. 2. Read each card carefully and match the statements with their explanations. Discuss with your partner whether you think each match is a benefit or a risk of GM plants. 3. Considering carefully the benefits and risks, you must give a reasoned argument for or against the use of GM plants, which you and your partner will share with the rest of the class. You should consider the effects on human health, the impact on the environment and benefits or risks to society. 4. Now complete the GM Plants Summary Sheet and glue it into your jotter. 12
Glossary of Terms Biodegradable Biofuel Conifer DNA Enzyme Genetic Modification (GM) Herbicide Native Pesticide Pharmaceutical Resistance Trait Type of waste that can be broken down by living organisms A fuel produced from plant or animal material Type of plant with evergreen leaves and seed-bearing cones Component of chromosomes and the material from which genes are made A chemical produced by living organisms that speeds up the rate of a chemical reaction but remains chemically unchanged at the end of the reaction Also known as genetic engineering, this involves the transfer of genetic information from one species to another A chemical designed to destroy and stop the growth of weeds, grasses and other plants Belonging naturally to a place A substance used for destroying insects or other organisms harmful to cultivated plants A chemical made for use as a medical drug Term used to refer to an organism which is unaffected by a disease or chemical substance A characteristic or quality 13