4.3 – Carbon Cycling Presentation
I designed this IB Biology PowerPoint presentation to correspond to the course companion, 2014 Edition Biology, written by Andew Allott and David Mindorff. The content in the presentation is also in alignment with the new 2016 exam. According to the IB Biology Guide, the following are addressed in this presentation:
Nature of Science topic:
• Making accurate, quantitative measurements—it is important to obtain reliable data on the concentration of carbon dioxide and methane in the atmosphere.
• Autotrophs convert carbon dioxide into carbohydrates and other carbon compounds.
• In aquatic ecosystems carbon is present as dissolved carbon dioxide and hydrogen carbonate ions.
• Carbon dioxide diffuses from the atmosphere or water into autotrophs.
• Carbon dioxide is produced by respiration and diffuses out of organisms into water or the atmosphere.
• Methane is produced from organic matter in anaerobic conditions by methanogenic archaeans and some diffuses into the atmosphere or accumulates in the ground.
• Methane is oxidized to carbon dioxide and water in the atmosphere.
• Peat forms when organic matter is not fully decomposed because of acidic and/or anaerobic conditions in waterlogged soils.
• Partially decomposed organic matter from past geological eras was converted either into coal or into oil and gas that accumulate in porous rocks.
• Carbon dioxide is produced by the combustion of biomass and fossilized organic matter.
• Animals such as reef-building corals and mollusca have hard parts that are composed of calcium carbonate and can become fossilized in limestone.