General Knowledge
What feedback loop occurs when thawing permafrost releases stored carbon, accelerating climate warming?
Positive feedback
Which two processes of the carbon cycle occur on both land and water?
Photosynthesis and respiration
What is the carbon cycle?
The movement of carbon around the biosphere
Excess carbon dioxide concentrations in the atmosphere leads to:
Global warming
What percent of an organism's body weight is carbon?
20%
What is formed when inorganic carbon sediments precipitate out of the water?
sedimentary rock
Which process follows burial and brings fossil fuels up to the surface?
Extraction
What human activity has the greatest impact on the carbon cycle?
Combustion (of fossil fuels)
What human activity contributes to both carbon emissions and reduces the planet’s capacity to absorb carbon dioxide?
Deforestation
Name all 7 processes of the carbon cycle
Photosynthesis, Cellular respiration, extraction, combustion, Burial, sedimentation, exchange
Carbon is found in organic macromolecules essential to life. Name one type of macromolecule carbon is found in.
Proteins, carbohydrates, lipids, or nucleic acids
Name a resource that if overharvested can lead to upsetting the balance of carbon in the atmosphere:
Overharvesting of trees, natural gas, coal, fossil fuels
Compare the residence time of carbon in the atmosphere versus the lithosphere (is it shorter in the atmosphere or lithosphere?)
Carbon spends a shorter time in the atmosphere (years to decades) whereas it spends a much longer time in the lithosphere (millions of years).
Name and define the process that forms the fossil fuels that we extract/use?
Sedimentation: calcium carbonate precipitates out as sediment & settles on ocean floor, while some are buried and become fossil fuels
What is the term for the process where carbon dioxide is converted into an organic form, typically by photosynthetic organisms?
Carbon fixation
______ emissions of carbon dioxide account for around 11% of global greenhouse gas emissions.
Agriculture-related