4.3.U1 Autotrophs convert carbon dioxide into carbohydrates and other carbon compounds.
4.3.U2 In aquatic ecosystems carbon is present as dissolved carbon dioxide and hydrogen carbonate ions.
4.3.U3 Carbon dioxide diffuses from the atmosphere or water into autotrophs.
4.3.U4 Carbon dioxide is produced by respiration and diffuses out of organisms into water or the atmosphere.
4.3.U5 Methane is produced from organic matter in anaerobic conditions by methanogenic archaeans and some diffuses into the atmosphere or accumulates in the ground.
4.3.U6 Methane is oxidized to carbon dioxide and water in the atmosphere.
4.3.U7 Peat forms when organic matter is not fully decomposed because of acidic and/or anaerobic conditions in waterlogged soils.
4.3.U8 Partially decomposed organic matter from past geological eras was converted either into coal or into oil and gas that accumulate in porous rocks.
4.3.U9 Carbon dioxide is produced by combustion of biomass and fossilized organic matter.
4.3.U10 Animals such as reef-building corals and Mollusca have hard parts that are composed of calcium carbonate and can become fossilized in limestone.
4.3.A1 Estimation of carbon fluxes due to processes in the carbon cycle.
4.3.A2 Analysis of data from air monitoring stations to explain annual fluctuations.
4.3.S1 Construct a diagram of the carbon cycle.
4.3.NOS Making accurate, quantitative measurements-it is important to obtain reliable data on the concentrations of carbon dioxide and methane in the atmosphere.
In the News: