Metabolism Autotrophs such as plants can construct the complex organic molecules in cells such as polysaccharides and proteins from simple molecules like carbon dioxide and water. Heterotrophs, on the other hand, require a source of more complex substances, such as monosaccharides and amino acids, to produce these complex molecules. Organisms can be further classified by ultimate source of their energy: photoautotrophs and photoheterotrophs obtain energy from light, whereas chemoautotrophs and chemoheterotrophs obtain energy from inorganic oxidation reactions. Photosynthesis is the synthesis of carbohydrates from sunlight and carbon dioxide (CO). In plants, cyanobacteria and algae, oxygenic photosynthesis splits water, with oxygen produced
Ocean storage of carbon dioxide Ocean storage of carbon dioxide Ocean storage of carbon dioxide (CO) is a method of carbon sequestration. The concept of storing carbon dioxide in the ocean was first proposed by Italian physicist Cesare Marchetti in his 1976 paper "On Geoengineering and the carbon dioxide Problem." Since then, the concept of sequestering atmospheric carbon dioxide in the world's oceans has been investigated by scientists, engineers, and environmental activists. 39,000 GtC currently reside in the oceans while only 750 GtC are in the atmosphere. Of the 1300 Gt carbon dioxide from anthropogenic emissions over the last 200 years, about 38% of that