Respiration
Respiration is the metabolic process by which organisms oxidize organic compounds (primarily glucose) to release energy for life processes while producing carbon dioxide and water as byproducts. It is the primary mechanism returning carbon from the biosphere to the atmosphere.
Real World
In Siberia's thawing permafrost, previously frozen organic matter is now being decomposed by microbial respiration, releasing CO2 and methane — a positive feedback loop that scientists estimate could add 0.3°C of additional warming by 2100.
Exam Focus
Always mention that decomposition (soil respiration) returns carbon to the atmosphere; link temperature rises to accelerated respiration rates for higher marks.
How well did you know this?