U.S. DEPARTMENT OF Energy Efficiency & ENERGY EDUCATION AND WORKFORCE DEVELOPMENT ENERGY Renewable Energy

Photosynthesis and Biomass Growth

(Seven Activities)

Grades: 9-12

Topic: Biomass

Owner: National Renewable Energy Laboratory

This educational material is brought to you by the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy. This lesson plan may contain links to other resources, including suggestions as to where to purchase materials. These links, product descriptions, and prices may change over time.

Photosynthesis and Biomass Growth

Science Content Standards: 5-8 For the Teacher Science As Inquiry - Content Standard A: Today, corn plants are being “Abilities necessary to do used to create a renewable energy source scientific inquiry” called ethanol. Ethanol is used in gas “Understandings about scientific tanks to power our cars and is one of the inquiry” leading alternatives to natural gas. We all Life Science know that Earth’s fossil fuel supply is – Content Standard C: finite, so fuels like ethanol provide an “Regulation and behavior” essential replacement for petroleum “Populations and ecosystems” products. Plant research is the starting “Diversity and adaptations of point for alternative fuel production. organisms” Throughout NREL’s Biofuels Program, Science and Technology scientists are uncovering ways to – Content Standard E: transform plant biomass into innovative “Abilities of technological and beneficial materials, such as fuel, design” plastic, and fiber. In addition, biomass “Understandings about science research is necessary for efficient food and technology” production and for understanding the Science in Personal and Social numerous other products that plants Perspectives provide. – Content Standard F: Introduce your students to the “Personal health” power of plants! Photosynthesis is “Populations, resources, and arguably the most important energy environments” transformation and is a fundamental “Natural hazards” concept for students of all ages. Projects “Risks and benefits” listed in this section should be used as an “Science and technology in exciting starting point for both classroom society” and science fair projects. Most of the Science Content Standards: 9-12 materials are easily obtainable at your Science As Inquiry local home or garden center. We - Content Standard A: encourage you to modify the experiments Abilities necessary to do scientific to fit your curriculum needs. inquiry” “Understandings about scientific National Science Education inquiry” Standards by the National Academy of Sciences

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Life Science When you breathe, your body - Content Standard C: uses oxygen (O2) and gives off carbon “Interdependence of organisms” dioxide (CO2). Since all animals “Matter, energy, and organization breathe in oxygen, why don’t we ever in living systems” run out? During photosynthesis, plants Science and Technology use carbon dioxide and release oxygen, so animals and plants have a – Content Standard E: “Abilities of technological design” symbiotic relationship; we rely on each other to survive! “Understandings about science and

technology”

Science in Personal and Social Photosynthesis Perspectives – Content Standard F: “Personal and community health” “Population growth” “Natural resources”

“Environmental quality” Plants, trees and aquatic algae “Natural and human-induced all create energy (in the form of hazards” glucose) through photosynthesis. “Science and technology in local, Since people can’t make their own national, and global challenges” energy from the sun, we eat food instead. We can use the energy Technology Description stored in plants in other ways too! Scientists are interested in biomass Why are plant leaves green? How energy for things such as fuel for your do plants get the energy to live? Do car. Biomass can be found all over the plants “breathe”? All of these questions world and there is an endless supply can be answered with one idea, since it can keep growing! Things such photosynthesis. Photosynthesis is a as corn stalks that are leftover from process where plants take the sun’s light harvesting, and forest brush that may energy and change it into glucose, a kind cause a fire hazard, can be converted of sugar. A green chemical in the in plant into fuels. These biomass fuels burn leaves, called chlorophyll, makes it all cleaner than gas or oil does, so it is happen and gives plants their green color. also safer for the environment. The only problem is that right now biomass fuels are not as economical (or cheap) as we would like. Scientists are trying to find ways to grow biomass where they can get the most energy with the lowest cost. Can you discover some ways in which we should grow biomass? Use the ideas below or come up with your own!

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Glucose: Sugar created in Resources: photosynthesis and the main energy source for our bodies. (C6H12O6) Arizona State University Photosynthesis Research Interdependence: Relying on each http://photoscience.la.asu.edu/photosyn/ other. default.html Photosynthesis: “Putting together Department of Energy Biomass Site with light.” This process uses http://www1.eere.energy.gov/biomass/ sunlight to create chemical energy (sugar) in plants and some Department of Agriculture Biofuel Site other organisms. http://ttic.nal.usda.gov/nal_display/index. php?info_center=6&tax_level=1&tax_subj Pigment: Coloring or dye. ect=318 Chlorophyll is a green pigment.

State of Florida Agricultural Science Pollutants: Waste material that http://www.florida­ contaminates air, soil or water. agriculture.com/PlanetAg/ Symbiotic: Organisms mutually needing or helping each other. Vocabulary Variable: Something that is changed.

Biomass: Plant material, vegetation, or Wetland: A lowland area, such as a agricultural waste used as a fuel or marsh or swamp that is saturated with energy source. moisture.

Chlorophyll: Green pigment in the Chloroplast that aids in creating sugar (glucose) from sunlight. Projjectect Ideas Ideas

Chromatography: A process used to separate mixtures by differences in 1 How do modern farming absorbency. techniques affect the growth of biomass? Control: A standard of comparison for checking or verifying the results of an Learning Objectives: The experiment. population of the Earth continues to grow about 7.4 million people a year, Ecosystem: Organisms and their and reached 6.3 billion people in 2003 environment functioning as a whole. (HTTP://WWW.CENSUS.GOV/). That is a lot of mouths to feed! With new advances in science and technology,

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we are able to create crops that are bigger and better through genetic Choose one or more of the alterations, pesticides, new fertilizers and following: synthetic (or fake) hormones. As the Plant hormone (Gibberellin: Sigma population of the world continues to $25.00) increase and farming area decreases, there is a widespread need for farmers to “Miracle Grow” (All purpose produce “miracle crops.” This project will fertilizer: Home Depot $4.00) help you discover and understand the benefits and problems that arise with crop Pesticides (Ortho Insect and modifications. Disease Control: Home Depot $14.00) Control and Variables: In this project, you will be selecting one or more modern Safety and Environment farming technique to look at more closely. Requirements: When using You can choose to do several, however materials such as insecticides and you must remember that you will need to hormones, gloves and safety glasses have a control setup so that you can should always be worn. Some plant compare your results to the control (the hormones, such as Gibberellin, are control would have no modifications). To poisonous, so they should not be used start, you will set up one growth chamber on food plants that will be eaten. (like an aquarium or large glass container) With all experiments, be sure to wash with several plants, using a modern hands thoroughly after application and farming technique. Set up another handling. growth chamber the same as the first, but do not add a modern farming technique. Suggestions: Since you will want to Then you can compare the two results. look for changes in growth, plants in You may also choose to do more the different growing chambers should than one modification, such as “how do be as similar as possible. You can use pesticides and hormones affect plant a scale to weigh biomass before and growth.” In this case, be sure to have a after the experiment. Regular control with no modifications, a control observations will identify other with just pesticide treatment and another changes as well, so a journal will help with just hormone treatment. This way to keep track of changes such as you can see what changes occurred when colors, leaf conditions, general they were separate and which ones only appearance and smell. occur when they are used together. Other Ideas: After you have looked Materials and Equipment: at the affects of a modern farming Growth Chambers (2 minimum) technique on your plant species, try a different species, such as a food plant Plants (3-4 per growth chamber) or a flowering plant. Are the effects the same as what you saw before? Scale

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How do aquatic plants react to the same pigments reflect or absorb the variable? wavelengths resulting in the wide There are also other ways to avoid variety of plant color. In this pests, such as biological controls. This is experiment, discover what happens when a predator of the pest is brought when plants are grown under various into the area to get rid of the problem. types of light. Will different light What are the risks and advantages to this sources generate a change in the size, method? Would they be less risky? color and rate of the growth Would this method be as quick or cost responses? efficient as a pesticide? In addition, consider having a Control and Variables: discussion about genetically engineered Controls: Plant type, temperature, food crops, such as those that produce amount of light, and planting medium their own pesticides. Should they be used should all be the same. Collect the data for food? What is the controversy at the same time for all plants. between organic and non-organic Variables: Different types of light. products? How do your results make you Water according to the plants needs. feel about these issues?

Resources: Materials and Equipment: Prism (www.boreal.com, $6.00) Carson, Rachel (1962) Silent Spring Note: This book may not be Light fixtures (Home Depot, $10.00 appropriate for all age levels each)

EPA fact sheets and current pesticide Grow light bulb (Home Depot, information: $10.00 each) http://www.epa.gov/pesticides/ Fluorescent bulb Current issues and problems facing the use of pesticides: Incandescent bulb http://www.beyondpesticides.org Rapid radish seeds 2 Is natural sunlight, imitation (www.boreal.com, $10.00/50) sunlight, fluorescent light or incandescent light best for 16 mini peat plant pots plants? Potting Soil Learning Objectives: In this activity, Labels students observe how sunlight separates Graph paper into a variety of colors when passed through a prism, and these visible colors correspond to different wavelengths in the electromagnetic spectrum. Plant

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Sample Data Table NUMBER DATE HEIGHT COLOR OF LEAVES

Safety and Environmental 3 How does varying the CO2 Requirements: Electrical shocks and levels affect the rate of growth in serious injury can occur if the light plants? fixtures are mishandled. Adult supervision is necessary! Learning Objectives: Understanding how carbon dioxide (CO2) levels affect Suggestions: biomass growth is key to understanding • Grow four radish seedlings under each environmental concerns such as global light source. Collect data after warming, rainforest destruction and germination for 3-6 weeks. much more. Since carbon dioxide is • You are encouraged to run this often released into the environment by experiment with a variety of plant factories, cars and natural processes, it types, such as coleus, geraniums, or is important to know how plants will sunflowers. react to changes in the air. • Does reflected light also impact plant growth? Design an experiment to see if Control and Variables: When setting tomatoes produce more fruit surrounded up your experiment, run a control as by red plastic mulch; cucumbers and well. In this project, you would have cantaloupe surrounded by blue! one aquarium with plants in it and an outside carbon dioxide source. Another Good sources of information about aquarium would be set up the same plants and gardening products way, but without the carbon dioxide. include: Remember to keep the soil, temperature, moisture levels and time Fun site that shows videos of seed run the same for both aquariums. Try germinations: to keep the plants as close to the same http://sunflower.bio.indiana.edu/~rhanga as possible, with the species, size and rt/ number of leaves all similar.

Colored mulch gardening supplies http://www.gardeners.com/ Materials and Equipment: 2 Aquariums or other types of Organic garden supplies growth chambers (Even 2 large http://www.seedsofchange.com/ glass jars will work!)

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Thermometer affect the growth of plants in different regions of the world, such as high At least four plants with a minimum of elevations, deserts, rainforests, and 5-6 leaves per plant tundra?

CO2 Source: Good sources of information Dry ice can be purchased at places about global warming include: that sell ice, such as grocery or ice cream stores. If your school has a CO2 cylinder, that EPA Climate Change Website for Kids: would also work well. http://epa.gov/climatechange/kids/ind ex.html Safety and Environment Requirements: Dry ice can cause severe Rainforest Action Network for Kids: burns, so be sure to always have adult http://www.ran.org/kids_action/ supervision and insulated gloves. Dry ice is a solid form of CO2, so it gives off CO2 gas (which is what we want for this project). Be sure that the room you are working in is ventilated well and you have a fresh supply of air. Also, CO2 compressed cylinders are under a lot of pressure and should be handled with great care.

Suggestions: Plants should have a minimum of 5-6 leaves and be of about equal size. Calculate total leaf area at beginning and end of the experiment for each plant (graph paper may be useful). If dry ice is used, consider that CO2 is heavier than air. Like its name suggests, dry ice is very cold (-109.3 °F or -78.5 °C) 4 What are the true colors of so the gas from the ice may be too cold leaves? for your plants, depending on how you set up your experiment. Learning Objective: This Other Ideas: Collect data in varying experiment uses chromatography concentrations of CO2 to find a pattern of techniques to separate the pigments biomass growth. Graph the results and found in leaves. Students come away see if you can find a fitting equation (if with an understanding of extraction you have a math background). According methods and information on the three to your results, how will global warming main groups of plant pigments:

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chlorophyll (green), carotenoids (yellow­ dark. The transferred pigment orange) and anthocyanins (blue-red). should be placed above the solvent level, with about 1 cm of the strip Control and Variables: in the solvent. Tape the strip to the Controls: Rubbing alcohol solvent top of the jar. Remove once the Variables: Variety of plant material solvent reaches the top; dry for comparisons. • Discuss the fact that the reds, yellows, and oranges that we see in fall are always present in leaves, but are obscured by the green of chlorophyll in spring and summer. Green bananas show chlorophyll too! As the chlorophyll breaks down the yellow pigments can be Materials and Equipment: seen. Coffee filters, cut 2-3 cm wide into • Conduct this test with leaves grown approximately 10 cm long strips in Project 2. (depending on jar size). • Scientists at NREL use solvents such as water and alcohol to Assortment of leaves and petals separate the chemicals in biomass. Can you design an experiment to Tape capture a plant’s fragrance?

Pencil Recommended plants: lavender, rosemary, rose petals Small clear jar Recommended solvents: Rubbing alcohol Sunflower oil, olive oil or hot water. Safety and Environmental Requirements: Use caution when • Here’s a great using alcohol! It is flammable and demo! Tea is a should not be splashed into eyes or on solution that skin. Goggles, gloves and a protective extracts plant lab coat are needed! compounds to flavor water. The sugar that Suggestions: we generally use to sweeten tea • Place the leaf upside down. At a spot is sucrose. Amazingly, when you 2 cm from the bottom of the filter add the sucrose to hot tea, there is strip, rub gently on the leaf with the a chemical reaction changing pencil point. Make the rubbing sucrose to two other sugars: approximately the size of a penny. Re­ glucose and fructose. These two adjust the leaf and continue rubbing sugars make tea nearly 10% until the spot on the filter paper is

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sweeter than tea that was sweetened 6 Jars or glass containers when cold! Scale

5 How do aquatic plants survive Dissolved Oxygen (DO) Test Kit underwater? Do they still need (DO meter may be substituted) light to make oxygen? (PETCO: $12.00)

Learning Objectives: We know that UV light source (Must be available plants need sunlight 24 hours/ day) for photosynthesis.

What happens when Pipette the plants are underwater? In this Thermometer activity, you will discover how aquatic Beta Fish or goldfish for the end of plants react to the activity (optional) different intensities of

light. Following this activity you will also Safety and Environment be able to set up an aquarium with Requirements: Always use safety aquatic plants and organisms in order to glasses and gloves when working with demonstrate the interdependence of chemicals and heat. plants and animals.

Control and Variables: In order to Suggestions: Set up 6 jars with understand what happens to aquatic equal volumes of water and biomass. plants when they are placed in sunlight, Place two jars in 24 hours of UV light, you will be setting up a wide range of two jars in 24 hours of darkness, and aquatic plant samples. In your two in 12 hours of UV light and 12 containers, you should have the same hours in darkness. Measure the volume of water and amount of plants so dissolved oxygen (DO) levels every 24 that you can compare the results between hours and record. Get DO levels the control and variables. Also, make before starting your experiment also sure the water and plants are from the so that you can see if it has changed same supply. Try to keep the conditions over time. Where is the dissolved for all the containers as close to the same oxygen going to or coming from? as possible. Different temperatures and What does this mean in a freshwater light sources will make plants act environment? Do the DO levels differently. increase, decrease or stay the same over time? Materials and Equipment: Aquatic plants: Elodea can be found in Other Ideas: After running your many ponds. It can also be purchased experiment, consider how aquatic and at pet stores for about $1.75/ plant. terrestrial (land) systems are similar and different. Create an aquatic

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ecosystem using the oxygen and carbon Variables: Similar plants grown in dioxide cycle that we have learned about. small, congested areas, 2” pots How would you create an ecosystem on recommended with up to 4 plants land? Consider moving life to Mars or to the International Space Station. What Materials and Equipment: would you need to live in either of those Up to 24 sets of plants (Use places? vegetables grown from seeds or a variety of house plants) Resources: 6 2” pots Information about the International Space Station (including sighting information) 6 6” pots can be found at: http://spaceflight.nasa.gov/station/ Potting soil

Lots of information about water systems Metric Ruler and biomes of the world: http://mbgnet.mobot.org/ Graph Paper

6 What happens when plants are 2 Root-Vue Farms (Optional) (www.Boreal.com, $52.00) crowded?

Safety and Environmental Learning Requirements: No special Objective: requirements needed. When we have plants in our Suggestions: house, we usually Use the data generated from only have one or this experiment to compare and two plants in each pot. However, in many contrast growth patterns between ecosystems there are lots of plants and crowded and uncrowded plants. trees crowded together. This is one Plants are amazing in how they reason why the rainforest is so amazing! can survive under adverse conditions. In this experiment, you will document In the rainforests, understory plants ways in which plants change their growth devised ways of using just one fleck of strategies to compensate for lack of light to provide the energy for growth nutrients, light and root space. Can you and reproduction. This system took think about ways that plants survive in millions of years to evolve. Identify the crowded conditions? structural differences between plants

that like shade and plants that need Control and Variables: full sun. Controls: Plants grown without • What short-term strategies did crowding your plants exhibit? Did your vegetable plants produce seeds?

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Plants that are stressed often try to Control and Variables: reproduce before their nutrients are Controls: Container of cattails lost. How is this triggered? without any pollutants. • Take one medium-sized plant and Variables: Similar plants treated with remove one leaf at a regulated rate to pollutants. represent predation. How many leaves can be “eaten” before the plant Materials and Equipment: changes? 4 6”containers of cattails or • Bonsai trees first appeared over a bulrushes (Approximately $25.00 in thousand years ago! It is an ancient local garden centers) practice first started by the Chinese where plant For every 2 liters of water add: roots are ½ cup sunflower oil restricted from 1 cup sand and soil mix growing, so the plant does Epson salt (optional) not have

enough Graph Paper nutrients to develop naturally. You may want to Metric Ruler research bonsai trees and start your own bonsai tree project! Saucers to collect runoff Resources: water

Rainforest Education Bucket (optional) http://www.rainforesteducation.com/ Safety and Environmental American Bonsai Society Requirements

HTTP://WWW.ABSBONSAI.ORG/ No special requirements needed.

Suggestions: 7 Can a cascade of wetlands be a • First, measure and record the pollution solution? height and health of your plants. • In this experiment, the first Learning Objectives: “wetland” should be watered with Often overlooked in the past, wetland the polluted water. Runoff water ecosystems are now recognized as playing from the first is then used to water a vital part in earth’s water cycle. Through the second, and so on. Document this exercise, children gain an the characteristics and volume of understanding of the complexity of the each watering. wetlands and measure the impact of • Water the plants three to seven pollution on common wetland species. days with the polluted water,

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documenting changes in the plants. Florida State University Wetland What happened to the sediments? Research Center: Where is the oil deposited? Are all the http://aquat1.ifas.ufl.edu/welcome.ht plants alive? Are the pollutants hurting ml them? • Irrigated agricultural lands often leave More Project Ideas salt residue in the soil. Will high salt concentrations harm plant growth? If time is available, use salt as a What growing medium produces more pollutant and check the impacts after biomass: regular soil or a hydroponic a few months. solution? • Wetlands are not just cattails marshes; there are untold What percentage of a plant's mass varieties of plant and nutrients are contained in its species in these roots? Stems? Leaves? ecosystems. Would a floating Collect soils from across your state plant, such as and run soil tests on each. Make a duckweed or prediction on which agricultural crop water hyacinths, would grow best in each soil. help the cattails filter the pollutants? Explain why. How do plants climb? Do plants grow • What are the current laws regarding toward light? How does light direction wetlands? Can a developer fill one in effect plant growth? to build a house? What about the birds and animals that live there? • Search the Internet to find a city that Test inorganic vs. organic growing uses wetlands in their water techniques. purification systems. How much can you dilute a pesticide while retaining its effectiveness? Resources: How successful are natural pest Environmental Protection Agency wetland deterrents? homepage http://www.epa.gov/OWOW/wetlands/ind What are the fastest growing grasses ex.html in your area? Trees?

In-depth information on Midwestern What factors positively influence seed wetlands: germination? Experiment with http://www.npwrc.usgs.gov/resource/199 variables such as seed orientation, 8/mnplant/mnplant.htm planting depth, or soil types, temperature.

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What are the effects of magnetic or electrical fields on plant development?

Do different size seeds have different germination rates? How strong are germinating seeds? Does the size of the seed correspond to the final size of the plant?

Which edible seeds sprout in water? Will frozen seeds sprout?

Place uncut, hydroponically grown tomatoes near grow lights for a few weeks and see if you can make the seeds sprout inside the tomato!!

What are the effects of oil, salt or bleach on algal growth?

Which plants and vegetables make the best dye?

References

National Renewable Energy Laboratory, Science Projects in Renewable Energy and Energy Efficiency. Boulder, CO, 1991 American Solar Energy Society, pp. 41-45.

Unknown, “Experiment of the Week - Sweet Tea #220” in The Teacher’s Corner, 2001 May 13, [Cited 2003 July 8], Available: http://www.theteachers corner.net/science/experiments/tea.htm

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