SCIENCE 101_ CARBON CYCLE GIZMO (Complete and Full Answers to Questions from Activities A, B, and C) Graded A

Format responses in blue bold font. Student Exploration: Carbon Cycle Vocabulary (refer to vocab file located on the Gizmo site for definitions): atmosphere, biomass, biosphere, carbon reservoir , carbon sink, fossil fuel, geosphere, greenhouse gas, hydrosphere, lithosphere, photosynthesis Prior Knowledge Questions (Do these BEFORE using the Gizmo.) In the process of photosynthesis, plants take in carbon dioxide (CO2) from the atmosphere and water (H2O) from the soil. Using the energy of sunlight, plants build molecules of glucose (C6H12O6) and oxygen (O2). 1. How do plants on Earth affect the amount of carbon in Earth’s atmosphere? They absorb it 2. Animals eat plants and produce carbon dioxide and water. How do animals affect the amount of carbon in Earth’s atmosphere? They produce it Gizmo Warm-up The Carbon Cycle Gizmo™ allows you to follow the many paths an atom of carbon can take through Earth’s systems. To begin, notice the black carbon atom in the Atmospheric CO2 area, highlighted in yellow. The glowing blue areas represent possible locations the carbon atom could go next. 1. From Earth’s atmosphere, where can the carbon atom go next? Ocean, land plants, and exposed rocks. 2. Click on Land plants and read the description. How did the carbon atom get from the atmosphere to a plant? Through photosynthesis 3. Select Land animals. How did the carbon atom get from land plants into the animal? Land animals eat plants since most carbon is stored in wood a small amount is eaten. 4. Select Atmospheric CO2. How did the carbon atom get from land animals back to the atmosphere? Through cellular respiration they produce energy and carbon dioxide and water is released. Activity A: Carbon pathways Get the Gizmo ready: • Click Reset. Introduction: Earth can be divided into four systems. The atmosphere is the air above Earth’s surface. The hydrosphere is composed of all of Earth’s water. The geosphere is the rocky, non-living part of Earth. The biosphere consists of all living things, including people. Some scientists use the term “anthroposphere” to describe everything made or modified by humans. Question: How does carbon move between the atmosphere, hydrosphere, biosphere, and geosphere? 1. Explore: Use the Gizmo to create a path for carbon that begins and ends in the atmosphere. Fill in the steps in the path below. Then, label each location with the system it represents. Finally, summarize very briefly how the carbon atom got to that location. Carbon path System How it got there Atmospheric CO2 Atmosphere Atmospheric CO2 comes from volcanoes, burning fossil fuels, and other sources. Land Plants/Animals Biosphere Plants go through photosynthesis. Animals eat plants to gain energy. Shells/Coral Biosphere There needs to be a good balance of dissolved CO2levels because if there is too much in the ocean then it can cause the ocean to be too acidic. The shells/coral/marine animals get this dissolved oxygen for forming and strengthening their shells/bones Sediments Geosphere Soil washed into streams and build up under water masses. Lithosphere Geosphere Sediments get compressed into sedimentary rocks that are rich in carbon. volcano Geosphere Rocks melt underground and release CO2 which is mixed into magma. Atmospheric Atmosphere Volcano erupts putting CO2, back into the atmosphere. Scroll down the file to continue Activity A 2. Create: Click Reset. Use the Gizmo to create a path in which the carbon atom goes from the atmosphere to the hydrosphere, biosphere and geosphere. Describe each transition briefly. Atmosphere Hydrosphere Biosphere Geosphere Atmospheric CO2 Oceanic CO2 Marine plants/algae Sediments Volcanoes, burning fossil fuels, and other sources. Cold temperatures from the ocean dissolves CO2 and stores it into deep waters. Plants and Algea go through photosynthesis. Plants and algae sink to the bottom of ocean building up large amounts of carbon 3. Explore: Use the Gizmo to create three more carbon paths, each starting and ending in the atmosphere. Label each location with A for atmosphere, B for biosphere, G for geosphere, or H for hydrosphere. (You can also use P for anthroposphere if you like, or just include it in the biosphere.) Path 1: (A) Atmospheric CO2→(B) land plants→(B) land animals→(A)atmospheric CO2 Path 2: (A) Atmospheric CO2→(G) exposed rock→(H) oceanic CO2→(B)marine plants/algae→(G) sediments→(P) petroleum→(A) lithosphere→(G) volcano→(A) Atmospheric CO2Path Path 3: (A) Atmospheric CO2→(B)land plants→(G) coal→(P) power plant→(A) atmospheric CO2 4. Explain: Based on the Gizmo, explain how the following transitions might take place: A. Describe at least two ways that carbon can get from a land plant to the atmosphere. a. Forest fires are one way in which carbon can pass from the ground plants to the atmosphere. Forest Fires happen all the time and carbon dioxide is emitted from the burning process that happens between the plants and the flames. Another way is that land animals absorb the carbon dioxide consumed by land plants and when most animals perform cellular respiration, the carbon dioxide is released in this process as a gas. B. Describe at least two ways that carbon can get from the atmosphere to the hydrosphere. a. One solution is to remove carbon dioxide naturally in cold ocean surface waters anyway, meaning that large water sources still have a carbon dioxide concentration. The second method is to dissolve carbon dioxide in rainwater that interacts with minerals in rocks later. Then these rocks are taken downstream through larger bodies of water through rivers or lakes and the carbon is transferred by the minerals in the rocks. C. Can you find two ways that carbon can get from the ocean to the lithosphere? (The lithosphere is the rigid layer of the Earth, including the crust and part of the mantle.) a. Because the ocean has a lot of biomass, photosynthesis can be carried out by aquatic organisms. They are part of the sediments, the plants that drift carbon to the bottom of the ocean. They will form into shaleand siltstone as the sediments contain a lot of carbon. And they're part of the lithosphere, these rocks. Another approach is for each of the species to use their shells for carbon dioxide. They get crushed into limestone as they pile on the ocean bottom, and the limestone is a part of the lithosphere. D. Describe at least two ways that carbon can get from seashells to the atmosphere. 1. Atmosphere → Hydrosphere → Shells/Coral → Hydrosphere→ Atmosphere a. Calcium carbonate shells are formed when CO2 is absorbed into the ocean, as previously described. These shells finally break, releasing their CO2, which returns to the ocean. This CO2 is released again, but as the cool ocean water warms up, it is released into the atmosphere this time. E. 2. Atmosphere → Hydrosphere → Shells/Coral → Limestone→ Cement plant → Atmosphere a. Limestone is used in cement and as mentioned before, limestone contains carbon from the calcium carbonate structures that pile, compress and layer into limestone. During the formation of cement, limestone is heated up which produces CaO which is used in the production of cement, and CO2 which Is unused in its production and thus released back into the atmosphere. Activity B: Human activities Get the Gizmo ready: • Click Reset. Introduction: Fossil fuels, such as coal, oil, and natural gas, formed over millions of years from the remains of ancient plants and animals. The burning of fossil fuels, as well as other human activities, increases the amount of carbon dioxide in the atmosphere. Question: How does human activity affect the carbon cycle? 1. Describe: Using the Gizmo, determine how coal and petroleum (oil) are formed. Describe the steps required to form each fuel from atmospheric CO2. Coal: atmospheric CO2 →land plants → coal Petroleum: atmospheric CO2→ oceanic CO2→ marine plants/algae → marine animals → sediments → petroleum 2. Explore: Natural gas is a mixture of methane (CH4), ethane (C2H6), and other gases. Find two ways that natural gas forms. List the steps of the two carbon pathways below: Path 1: land plants, natural gas Path 2: land plants, soil, sediment, natural How is the formation of natural gas related to the formation of coal and petroleum? They all have the same “ingredients” 3. Describe: Fossil fuels are used in many ways. Using the Gizmo, describe the main use for each fuel. Coal: generate electricity Petroleum: fuel vehicles and make plastic, Natural gas: generate electricity and heat homes In each case, what is the end product of burning the fossil fuel, and where does it go? To the atmosphere (Activity B continued on next page) Activity B (continued from previous page) 4. Explore: Another major contribution to atmospheric carbon dioxide is the cement industry. Using the Gizmo, find a carbon atom path from the atmosphere to the cement plant. (Hint: One of the ingredients in cement is limestone.) Path: How is carbon dioxide produced in a cement plant? Limestone is heated, producing calcium oxid and carbon dioxide 5. Analyze: Click Reset, then navigate to the Land animals. Select Atmospheric CH4. A. How do land animals create methane? When it dies its body is broken down by organism that release carbon B. Humans raise large numbers of cattle for food. How will these herds of cows affect Earth’s atmosphere? By it remain being eaten by organism it will release carbon 6. Analyze: In many tropical rainforests, people clear land by cutting down trees and burning them. After a few years, the soil runs out of nutrients and cannot be farmed any longer. How does this practice of “slash and burn agriculture” affect Earth’s atmosphere? It affects the atmosphere by burning fossil fuels which would make it bad for the environment in years would make the world bad. 7. Draw conclusions: In general, how do many human activities influence the carbon cycle? Almost all the human in the world Scroll down the file to complete Activity C Activity C: Modeling the carbon cycle Get the Gizmo ready: • Select the MODEL tab. Introduction: Humans have been burning fossil fuels rapidly for the past 250 years. As a result, the amount of atmospheric CO2 has increased by about 40% since the year 1800. By measuring how much carbon moves into and out of the atmosphere, scientists can predict the change in the amount of atmospheric carbon dioxide every year. Question: How can we model changes in atmospheric carbon over time? 1. Observe: The MODEL tab of the Gizmo shows a greatly simplified model of the carbon cycle. The ovals represent carbon reservoirs, where carbon is stored. The arrows represent the movement of carbon from one reservoir to another. A. What are the two major sources of atmospheric carbon? Natural and human activies B. A carbon sink is a location that stores carbon for a long period of time. What are two carbon sinks that remove carbon from the atmosphere? Water and plants C. The unit “GtC” stands for gigatonnes of carbon, where one GtC is equal to one trillion kilograms of carbon. Without making any changes to the Gizmo, list the carbon reservoirs from largest to smallest. Note: The largest carbon reservoir is actually Earth’s lithosphere, which contains about 80,000 GtC. However, there is not much exchange between the lithosphere and the other reservoirs on short time scales. 2. Experiment: If necessary, click Return to original settings. These settings approximate present-day conditions, but should not be taken as exact values. A. What is the total amount of carbon removed from the atmosphere each year by the ocean and land plants? 65 B. What is the total amount of carbon added to the atmosphere from soil and the burning of fossil fuels? +4 C. How much will atmospheric carbon change in one year? 4 In 10 years? 40 In 100 years? 1250 (Activity C continued on next page) Activity C (continued from previous page) 3. Calculate: Carbon dioxide is a greenhouse gas that helps to trap heat in Earth’s atmosphere. We need some CO2 in the atmosphere to maintain a warm planet, but excess carbon can cause considerable warming of the planet. A. What fossil fuel usage will result in no change in atmospheric CO2 each year? 75 B. What percentage decrease in fossil fuel usage is required to achieve this goal? 9 4. Experiment: Using the Gizmo model, explore the following questions: A. How does increasing plant biomass (amount of plants) affect atmospheric CO2? It decreases the CO2 B. How does increasing oceanic CO2 intake affect atmospheric CO2 and oceanic CO2? The oceanic increase put the atmosphere decreases. As carbon dioxide is absorbed by the ocean, the ocean becomes slightly more acidic. This could make it harder for many organisms to build their shells and skeletons. The consequences of ocean acidification are not yet fully understood. 5. Infer: Click Reset and Return to original settings. Suppose we completely stopped burning fossil fuels immediately. How many years would it take to return to atmospheric CO2 levels from the year 1800, about 600 GtC? Use the Gizmo to find the answer. 50 years 6. Think about it: Since hard-shelled organisms evolved about 550 million years ago, billions of tons of limestone rock have been produced from their shells. Limestone is made of calcium carbonate, with the formula CaCO3. Based on this, how do you think the amount of atmospheric CO2 has changed in the last 550 million years, and how has this affected Earth’s climate? Explain your answer. It has changed a lot since the world started. It has effected the change in the environment, and because of the atmosphere the ice is melting making the world hotter throughout the years. Complete the five-question quiz for this activity located under the Gizmo screen on the ExploreLearning website. Paste a screenshot of your quiz results below. Your score will be a part of your final grade for this assignment. Show Less