Query: This growth stimulation occurs because CO2 is one of the two raw materials (the other being water) that are required for photosynthesis.

Relevant passages:
Carbon dioxide <=SEP=> Carbon dioxide ( chemical formula ) is a colorless gas with a density about 60 % higher than that of air ( 1.225 g/L ) that is odorless at normally encountered concentrations . Carbon dioxide consists of a carbon atom covalently double bonded to two oxygen atoms . It occurs naturally in Earth 's atmosphere as a trace gas at a concentration of about 0.04 percent ( 400 ppm ) by volume . Natural sources include volcanoes , hot springs and geysers , and it is freed from carbonate rocks by dissolution in water and acids . Because carbon dioxide is soluble in water , it occurs naturally in groundwater , rivers and lakes , ice caps , glaciers and seawater . It is present in deposits of petroleum and natural gas .   As the source of available carbon in the carbon cycle , atmospheric carbon dioxide is the primary carbon source for life on Earth and its concentration in Earth 's pre-industrial atmosphere since late in the Precambrian has been regulated by photosynthetic organisms and geological phenomena . Plants , algae and cyanobacteria use light energy to photosynthesize carbohydrate from carbon dioxide and water , with oxygen produced as a waste product .   Carbon dioxide is produced by all aerobic organisms when they metabolize carbohydrates and lipids to produce energy by respiration . It is returned to water via the gills of fish and to the air via the lungs of air-breathing land animals , including humans . Carbon dioxide is produced during the processes of decay of organic materials and the fermentation of sugars in bread , beer and winemaking . It is produced by combustion of wood and other organic materials and fossil fuels such as coal , peat , petroleum and natural gas .   It is a versatile industrial material , used , for example , as an inert gas in welding and fire extinguishers , as a pressurizing gas in air guns and oil recovery , as a chemical feedstock and in liquid form as a solvent in decaffeination of coffee and supercritical drying . It is added to drinking water and carbonated beverages including beer and sparkling wine to add effervescence . The frozen solid form of , known as `` dry ice '' is used as a refrigerant and as an abrasive in dry-ice blasting .   Carbon dioxide is the most significant long-lived greenhouse gas in Earth 's atmosphere . Since the Industrial Revolution anthropogenic emissions - primarily from use of fossil fuels and deforestation - have rapidly increased its concentration in the atmosphere , leading to global warming . Carbon dioxide also causes ocean acidification because it dissolves in water to form carbonic acid .

Photosynthesis <=SEP=> Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that can later be released to fuel the organisms ' activities ( energy transformation ) . This chemical energy is stored in carbohydrate molecules , such as sugars , which are synthesized from carbon dioxide and water -- hence the name photosynthesis , from the Greek φῶς , phōs , `` light '' , and σύνθεσις , synthesis , `` putting together '' . In most cases , oxygen is also released as a waste product . Most plants , most algae , and cyanobacteria perform photosynthesis ; such organisms are called photoautotrophs . Photosynthesis is largely responsible for producing and maintaining the oxygen content of the Earth 's atmosphere , and supplies all of the organic compounds and most of the energy necessary for life on Earth .   Although photosynthesis is performed differently by different species , the process always begins when energy from light is absorbed by proteins called reaction centres that contain green chlorophyll pigments . In plants , these proteins are held inside organelles called chloroplasts , which are most abundant in leaf cells , while in bacteria they are embedded in the plasma membrane . In these light-dependent reactions , some energy is used to strip electrons from suitable substances , such as water , producing oxygen gas . The hydrogen freed by the splitting of water is used in the creation of two further compounds that act as an immediate energy storage means : reduced nicotinamide adenine dinucleotide phosphate ( NADPH ) and adenosine triphosphate ( ATP ) , the `` energy currency '' of cells .   In plants , algae and cyanobacteria , long-term energy storage in the form of sugars is produced by a subsequent sequence of reactions called the Calvin cycle ; some bacteria use different mechanisms , such as the reverse Krebs cycle , to achieve the same end . In the Calvin cycle , atmospheric carbon dioxide is incorporated into already existing organic carbon compounds , such as ribulose bisphosphate ( RuBP ) . Using the ATP and NADPH produced by the light-dependent reactions , the resulting compounds are then reduced and removed to form further carbohydrates , such as glucose .   The first photosynthetic organisms probably evolved early in the evolutionary history of life and most likely used reducing agents such as hydrogen or hydrogen sulfide , rather than water , as sources of electrons . Cyanobacteria appeared later ; the excess oxygen they produced contributed directly to the oxygenation of the Earth , which rendered the evolution of complex life possible . Today , the average rate of energy capture by photosynthesis globally is approximately 130 terawatts , which is about three times the current power consumption of human civilization .  Photosynthetic organisms also convert around 100 -- 115 thousand million metric tonnes of carbon into biomass per year .

Carnivorous plant <=SEP=> Carnivorous plants are plants that derive some or most of their nutrients ( but not energy ) from trapping and consuming animals or protozoans , typically insects and other arthropods . Carnivorous plants have adapted to grow in places where the soil is thin or poor in nutrients , especially nitrogen , such as acidic bogs and rock outcroppings . Charles Darwin wrote Insectivorous Plants , the first well-known treatise on carnivorous plants , in 1875 .   True carnivory is thought to have evolved independently nine times in five different orders of flowering plants , and is represented by more than a dozen genera . This classification includes at least 583 species that attract , trap and kill prey , absorbing the resulting available nutrients . Additionally , over 300 protocarnivorous plant species in several genera show some but not all of these characteristics .