The Carbon Cycle

Carbon Cycle CO2 in the atmosphere Car and factory emissions plant respiration animal respiration dead organisms and waste products fossil fuels decaying organisms organic carbon photosynthesis Fill in the missing words. Plants use CO2 in the process of photosynthesis to make sugar (glucose) and oxygen (gas). Animals use oxygen in the process of cellular respiration and make more CO2. The ocean is the main regulator of CO2 in the carbon cycle because CO2 dissolves easily in it. In the past, huge deposits of carbon were stored as dead plants and animals. Today these deposits are burned as fossil fuels, which include coal, oil, and natural gas. More CO2 is released in the atmosphere today than in the past because of the burning of fossil fuels. Another natural source for CO2 is methane. Too much CO2 in the atmosphere may be responsible for the greenhouse effect. Processes involved in the Carbon Cycle Match the name of the processes with their correct description. Photosynthesis process used by producers to convert solar energy, carbon dioxide, and water into sugars and oxygen Cellular respiration process by which heterotrophs convert chemical energy and oxygen into water, carbon dioxide, and ATP. Decomposition process by which organisms breakdown into organic compounds Combustion process by which carbon dioxide is released from fossil fuels Which of the following is true about the carbon cycle? Combustion reduces carbon dioxide gas. Respiration uses carbon dioxide gas. Decomposition recycles the carbon compounds in nature and produces carbon dioxide. Photosynthesis removes carbon dioxide from the atmosphere and makes organic matter. Which of the following increases the amount of carbon dioxide in the atmosphere? increased photosynthesis reduction of cellular respiration increased usage of fossil fuels increase in waste elimination by animals Which of the following would decrease the amount of excess carbon dioxide released into the carbon cycle? deforestation reduction of the use of fossil fuels increased cellular respiration by animals reduction in the photosynthetic activity of aquatic producers