The Carbon Cycle - AP Environmental Science

1. What is the primary source of anthropogenic CO2 emissions?

   Burning of fossil fuels. Human activities like coal, oil, and gas combustion.

2. Which process involves the breakdown of organic matter, releasing carbon into the soil?

   Decomposition. Bacteria and fungi break down dead material, releasing carbon.

3. Which process describes the conversion of organic carbon back into atmospheric CO2?

   Respiration. Cellular process breaking down glucose and releasing $CO_2$.

4. During which process do oceans release CO2 back into the atmosphere?

   Degassing. Warmer water releases dissolved $CO_2$ back to atmosphere.

5. What is the primary role of decomposers in the carbon cycle?

   Decompose organic matter, releasing CO2. Bacteria and fungi break down dead material, returning carbon to atmosphere.

6. In which form is carbon most abundantly found in the atmosphere?

   Carbon dioxide ($CO_2$). Makes up about 0.04% of atmospheric gases by volume.

7. Identify the process by which CO2 is converted into organic compounds by plants.

   Photosynthesis. Light-driven process converting $CO_2$ and water into glucose.

8. Which process releases CO2 back into the atmosphere from living organisms?

   Respiration. Cellular process where organisms break down glucose and release $CO_2$.

9. What is the primary form of carbon found in the ocean?

   Bicarbonate ions ($HCO_3^-$). Most oceanic carbon exists as dissolved bicarbonate ions.

10. Name the process where dead organisms are converted into fossil fuels.

    Fossilization. Dead organisms buried under sediments form coal, oil, and gas over time.

11. Identify the role of phytoplankton in the carbon cycle.

    Absorb CO2 during photosynthesis. Marine algae fix atmospheric carbon through photosynthesis.

12. How do fossil fuels form over geological time?

    From decomposed organic matter under pressure. Heat and pressure transform buried organic material over millions of years.

13. In which process is carbon transferred from the atmosphere to the biosphere?

    Photosynthesis. Plants remove atmospheric $CO_2$ and convert it to biomass.

14. What role do marine organisms play in the carbon cycle?

    They sequester carbon in shells and skeletons. Build calcium carbonate shells that store carbon long-term.

15. What is the main chemical component of fossil fuels?

    Carbon. Fossil fuels are primarily carbon compounds like hydrocarbons.

16. Which carbon compound is found in limestone and sedimentary rocks?

    Calcium carbonate ($CaCO_3$). Carbonate mineral formed from marine organisms' shells over time.

17. Which cycle describes the movement of carbon through living organisms and the environment?

    The carbon cycle. Movement of carbon between atmosphere, biosphere, and geosphere.

18. What is the chemical formula for carbon dioxide?

    $CO_2$. One carbon atom bonded to two oxygen atoms.

19. What is the impact of increased atmospheric CO2 on global temperature?

    Global warming. More atmospheric $CO_2$ enhances the greenhouse effect.

20. What is the process by which carbon dioxide is absorbed by ocean water?

    Dissolution. $CO_2$ dissolves in seawater forming carbonic acid and bicarbonates.

21. How does increased atmospheric CO2 affect plant growth?

    Enhances plant growth due to more photosynthesis. $CO_2$ fertilization effect increases photosynthetic rates.

22. What is the term for carbon stored in trees and plants?

    Biomass carbon. Carbon stored in living plant tissues and wood.

23. What is the result of increased greenhouse gases in the atmosphere?

    Enhanced greenhouse effect. More heat trapped leads to rising global temperatures.

24. Which process involves the conversion of gaseous carbon into solid carbon forms?

    Carbon sequestration. Removing atmospheric carbon and storing it in solid forms.

25. Which human activity significantly disrupts the carbon cycle?

    Deforestation. Removing forests reduces carbon storage and increases emissions.

26. Identify the largest carbon reservoir on Earth.

    Sedimentary rocks. Contains limestone and other carbonate minerals storing most Earth's carbon.

27. Which form of carbon is stored in the ocean?

    Dissolved inorganic carbon. Bicarbonates and carbonates dissolved in ocean water.

28. How does deforestation affect the carbon cycle?

    Increases CO2 levels in the atmosphere. Removing trees reduces carbon sequestration and adds $CO_2$ from burning.

29. Identify the process that removes carbon from the atmosphere and stores it underground.

    Carbon sequestration. Long-term storage of carbon in geological formations.

30. What is the process by which carbon is released during volcanic eruptions?

    Outgassing. Volcanic activity releases $CO_2$ stored in Earth's interior.

31. Identify the process that converts organic carbon into carbon dioxide in soils.

    Soil respiration. Microorganisms in soil decompose organic matter, releasing $CO_2$.

32. Which gas is primarily responsible for the greenhouse effect?

    Carbon dioxide ($CO_2$). Absorbs infrared radiation, trapping heat in Earth's atmosphere.

33. What is the effect of ocean acidification on marine life?

    Impairs shell formation in marine organisms. Lower pH dissolves carbonate shells and disrupts marine ecosystems.

34. What is the term for carbon stored in fossil fuels?

    Geological carbon. Carbon stored in coal, oil, and natural gas deposits.

35. What impact does increased CO2 have on the pH of ocean waters?

    Decreases pH (acidification). Dissolved $CO_2$ forms carbonic acid, lowering ocean pH.

36. Name the process that converts atmospheric CO2 into glucose in plants.

    Calvin cycle. Light-independent reactions that fix $CO_2$ into sugar molecules.

37. What is the process by which plants absorb CO2 during photosynthesis?

    Carbon fixation. The process where plants convert atmospheric $CO_2$ into organic molecules.

38. What is the process by which soil carbon is released as CO2 due to microbial activity?

    Microbial respiration. Soil microbes decompose organic matter, releasing $CO_2$.

39. What is the relationship between the carbon cycle and climate change?

    Increased CO2 leads to global warming. Excess atmospheric carbon enhances greenhouse warming.

40. Which human activity is the largest source of CO2 emissions?

    Burning fossil fuels. Combustion releases stored carbon from coal, oil, and natural gas.

Study these flashcards