6.1 The Carbon Cycle Flashcards
How much CO2 in atmosphere?
Terrestrial photosynthetic organisms:
remove? by?
return? by?
0.04%
Remove CO2 from atmosphere by photosynthesis
Return CO2 to atmosphere by respiration
Effect of humans/organisms on CO2 conc:
Why is atmospheric CO2 concentration increasing due to:
Combustion of fossil fuels? (1)
Deforestation (rainforests)? (3)
CO2 that was locked up in fuels released
Photosynthesising biomass removed
Less photosynthesis
Less CO2 removed from atmosphere.
Effect of photosynthesis/respiration on CO2 conc:
Why are there short-term fluctuations in proportion of CO2 and O2 in atmosphere?
Why is CO2 concentration greater at night? (2)
Why is CO2 concentration lower on a summer’s day?
variation in rates of photosynthesis and respiration.
No light = no photosynthesis
Respiration still occurs
More light = more photosynthesis
How much CO2 in oceans?
How does it keep atmospheric CO2 concentration constant? (2)
50X more than in atmosphere
Too high - CO2 dissolves into ocean.
Too low - CO2 enters atmosphere
The Carbon Cycle (6)
Producers take up carbon in form of CO2.
Producers incorporate carbon into carbon-containing compounds.
Producer eaten, carbon passes into consumer.
Consumer eaten, carbon passes into secondary/tertiary consumers.
Producers/consumers die, saprobiotic microorganisms (decomposers) break down their carbon-containing compounds
Release carbon in original form of CO2.
Decomposition:
Define saprobiotic microorganisms (decomposers)
Absorb molecules by?
Release CO2 by?
Organisms that break down complex organic molecules into simple organic molecules or ions by secreting enzymes onto them.
Diffusion
Respiration.
If organism not decomposed?
CO2 released upon?
What sink to bottom of oceans? forming?
CO2 released upon?
Fossilised
Combustion
Non-decomposable shells and bones, sedimentary rocks
Weathering