Carbon Cycle Flashcards
what is the carbon cycle?
the movement of atoms and molecules containing the element carbon (carbon dioxide, glucose, methane) between sources and sinks
what is the difference between some carbon reservoirs compared to others?
some of the reservoirs in which carbon compounds occur in the carbon cycle hold those compounds for long periods of time, while some hold them for relatively short periods of time
what is the mini-loop in the carbon cycle?
carbon cycles between photosynthesis and cellular respiration in living things
what is the major time discrepancy in the carbon cycle?
plant and animal decomposition have led to the storage of carbon over millions of years while the burning of fossil fuels quickly moves that stored carbon into atmospheric carbon, in the form of carbon dioxide; burial (the formation of fossil fuels) takes longer than extraction and combustion which means they increase the concentration of carbon dioxide in the atmosphere
what steps in the carbon cycle are quick? which ones are slow?
fossil fuel combustion is very quick while sedimentation and burial are very slow
the differences in the amount of time involved in each step of the carbon cycle leads to:
an imbalance in which reservoirs or sinks are storing carbons
what is a key reservoir of carbon?
the atmosphere
what happens if there are increasing levels of carbon in the atmosphere?
global warming
what is a carbon sink?
a carbon reservoir that stores more carbon than it releases
what are some examples of carbon sinks?
the ocean (algae and sediments), plants, soil
what is a carbon source?
processes that add carbon to the atmosphere
what are some examples of carbon sources?
fossil fuel (oil, coal, natural gas) combustion, animal agriculture (cow burps/farts release methane), and deforestation releases carbon dioxide from trees and prevents more atmospheric carbon from being absorbed
which organisms perform photosynthesis?
plants, algae, phytoplankton
what does photosynthesis do in the carbon cycle?
it removes carbon dioxide from the atmosphere and converts it to glucose
what is glucose?
a biological form of carbon, stored as chemical energy in the form of sugar
photosynthesis is a carbon dioxide __________
cellular respiration is a carbon dioxide __________
sink
source
which organisms perform cellular respiration and why?
done by plants and animals to release stored energy
cellular respiration uses __________ to break down __________ and release __________ which releases __________ into the __________
oxygen, glucose, energy, carbon dioxide, atmosphere
are cellular respiration and photosynthesis quick or slow processes?
they are both very quick
where and how do cellular respiration and photosynthesis cycle carbon?
they cycle carbon between the biosphere and atmosphere in balanced amounts so there is no net carbon increase in the atmosphere
what is direct exchange in the carbon cycle?
carbon dioxide moves directly between the atmosphere and the ocean by dissolving into and out of ocean water at the surface
is direct exchange a quick or slow process?
it is a very quick process
how is direct exchange in the carbon cycle balanced?
it happens in equal directions which balances levels of carbon dioxide between the atmosphere and ocean
what are the consequences of direct exchange?
an increase in carbon dioxide in the atmosphere leads to an increase in carbon dioxide in the ocean, leading to ocean acidification
how can carbon dioxide be taken out of the ocean?
through carbon sinks like:
- algae and phytoplankton take carbon dioxide out of the ocean and atmosphere through photosynthesis
- coral reefs and marine organisms with shells also take carbon dioxide out of the ocean to make calcium carbonate exoskeletons
- sedimentation
- burial
what is ocean sedimentation in the carbon cycle?
when marine organisms die, their bodies sink to the ocean floor where they’re broken down into sediments that contain carbon
what is burial in the carbon cycle?
over long periods of time, the pressure of water compresses carbon containing sediments on the ocean floor into sedimentary stone like limestone and sandstone; it’s a slow geological process that sores carbon in underground sinks like sedimentary rock or fossil fuels
burial/sedimentary stones are a:
long term carbon reservoir
how are fossil fuels formed?
coal, oil, and natural gas are formed from fossilized remains of organic dead matter like dead ferns (coal) or marine algae and plankton (oil)
what are the extraction and combustion steps of the carbon cycle?
digging up or mining fossil fuels and burning them as an energy source which releases carbon dioxide into the atmosphere
how does burial store carbon in underground sinks?
sediments like bits of rock, soil, and organic matter are compressed into sedimentary rock or fossil fuels by pressure form overlying rock layers or water
