Here is a broad set of photosynthesis facts expressed as **(subject, predicate, object)** triples.

I’ll keep the predicates fairly readable and consistent, and cover definition, location, stages, molecules, organisms, adaptations, ecology, and evolution.

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### Core definition

- (photosynthesis, is, biological process)
- (photosynthesis, converts, light energy into chemical energy)
- (photosynthesis, uses, carbon dioxide)
- (photosynthesis, uses, water)
- (photosynthesis, produces, carbohydrates)
- (photosynthesis, often produces, oxygen)
- (photosynthesis, stores energy in, chemical bonds)
- (photosynthesis, supports, most life on Earth)
- (photosynthesis, is performed by, plants)
- (photosynthesis, is performed by, algae)
- (photosynthesis, is performed by, cyanobacteria)
- (photosynthesis, occurs in, photoautotrophs)
- (photoautotrophs, use, light as energy source)
- (photoautotrophs, use, carbon dioxide as carbon source)

### Overall equation

- (oxygenic photosynthesis, has overall equation, 6 CO2 + 6 H2O + light -> C6H12O6 + 6 O2)
- (overall photosynthesis equation, is, simplification)
- (photosynthesis, actually produces first, triose phosphates)
- (glucose, is not always, direct immediate product of photosynthesis)
- (oxygen in released O2, originates from, water)
- (carbon in sugars, originates from, carbon dioxide)

### Major types

- (photosynthesis, includes, oxygenic photosynthesis)
- (photosynthesis, includes, anoxygenic photosynthesis)
- (oxygenic photosynthesis, releases, oxygen)
- (anoxygenic photosynthesis, does not release, oxygen)
- (oxygenic photosynthesis, uses, water as electron donor)
- (anoxygenic photosynthesis, may use, hydrogen sulfide as electron donor)
- (anoxygenic photosynthesis, may use, ferrous iron as electron donor)
- (anoxygenic photosynthesis, is found in, certain bacteria)

### Organisms and distribution

- (plants, perform, oxygenic photosynthesis)
- (algae, perform, oxygenic photosynthesis)
- (cyanobacteria, perform, oxygenic photosynthesis)
- (purple sulfur bacteria, perform, anoxygenic photosynthesis)
- (green sulfur bacteria, perform, anoxygenic photosynthesis)
- (diatoms, perform, photosynthesis)
- (dinoflagellates, may perform, photosynthesis)
- (euglenoids, may perform, photosynthesis)
- (marine phytoplankton, perform, large fraction of global photosynthesis)
- (phytoplankton, include, cyanobacteria)
- (phytoplankton, include, diatoms)
- (phytoplankton, include, coccolithophores)
- (photosynthetic organisms, are primary producers in, many ecosystems)

### Cellular location in plants and algae

- (photosynthesis in plants, occurs mainly in, chloroplasts)
- (photosynthesis in algae, occurs in, chloroplasts)
- (chloroplasts, are surrounded by, double membrane)
- (chloroplasts, contain, thylakoid membranes)
- (thylakoid membranes, enclose, thylakoid lumen)
- (stroma, surrounds, thylakoids)
- (light-dependent reactions, occur in, thylakoid membranes)
- (Calvin cycle, occurs in, stroma)
- (grana, are stacks of, thylakoids)
- (stroma lamellae, connect, grana)

### Leaf anatomy and gas exchange

- (photosynthesis in vascular plants, occurs mainly in, leaves)
- (mesophyll cells, contain many, chloroplasts)
- (palisade mesophyll, is specialized for, light capture)
- (spongy mesophyll, facilitates, gas diffusion)
- (stomata, allow entry of, carbon dioxide)
- (stomata, allow exit of, oxygen)
- (stomata, allow loss of, water vapor)
- (guard cells, regulate, stomatal aperture)
- (transpiration, is linked to, stomatal opening)
- (leaf veins, deliver, water)
- (leaf veins, export, sugars)

### Pigments

- (chlorophyll a, is primary pigment in, oxygenic photosynthesis)
- (chlorophyll b, is accessory pigment in, plants and green algae)
- (carotenoids, are accessory pigments in, photosynthesis)
- (phycobilins, are accessory pigments in, cyanobacteria)
- (phycobilins, are accessory pigments in, red algae)
- (chlorophyll, absorbs, visible light)
- (chlorophyll a, absorbs strongly in, blue light)
- (chlorophyll a, absorbs strongly in, red light)
- (chlorophyll, reflects, green light)
- (carotenoids, absorb, blue-green light)
- (carotenoids, provide, photoprotection)
- (antenna pigments, transfer excitation energy to, reaction center chlorophyll)
- (reaction center chlorophyll, initiates, photochemistry)

### Photosystems

- (oxygenic photosynthesis, uses, photosystem II)
- (oxygenic photosynthesis, uses, photosystem I)
- (photosystem II, is abbreviated as, PSII)
- (photosystem I, is abbreviated as, PSI)
- (PSII reaction center, is called, P680)
- (PSI reaction center, is called, P700)
- (PSII, absorbs best at, 680 nm)
- (PSI, absorbs best at, 700 nm)
- (photosystems, contain, antenna complexes)
- (photosystems, contain, reaction centers)
- (PSII, acts before, PSI in linear electron flow)

### Light-dependent reactions

- (light-dependent reactions, require, light)
- (light-dependent reactions, produce, ATP)
- (light-dependent reactions, produce, NADPH)
- (light-dependent reactions, release, oxygen)
- (light-dependent reactions, involve, electron transport chain)
- (photons, excite, chlorophyll electrons)
- (excited electrons, are transferred to, primary electron acceptors)
- (electron transport, contributes to, proton gradient)
- (proton gradient, drives, ATP synthesis)
- (ATP synthase, synthesizes, ATP)
- (NADP+, is reduced to, NADPH)
- (water splitting, replenishes electrons in, PSII)
- (water splitting, releases, protons)
- (water splitting, releases, oxygen)
- (water splitting, is catalyzed by, oxygen-evolving complex)

### Water splitting and oxygen evolution

- (oxygen-evolving complex, is associated with, PSII)
- (oxygen-evolving complex, contains, manganese cluster)
- (oxygen-evolving complex, oxidizes, water)
- (two water molecules, yield, one O2 molecule)
- (water oxidation, provides, electrons)
- (water oxidation, provides, protons)
- (released molecular oxygen, diffuses out of, chloroplast)
- (atmospheric oxygen, is largely derived from, oxygenic photosynthesis)

### Electron transport chain components

- (PSII, transfers electrons to, plastoquinone)
- (plastoquinone, transfers electrons to, cytochrome b6f complex)
- (cytochrome b6f complex, transfers electrons to, plastocyanin)
- (plastocyanin, transfers electrons to, PSI)
- (PSI, transfers electrons to, ferredoxin)
- (ferredoxin, transfers electrons to, ferredoxin-NADP+ reductase)
- (ferredoxin-NADP+ reductase, reduces, NADP+)
- (cytochrome b6f complex, contributes to, proton pumping)
- (electron transport chain, links, PSII and PSI)

### Photophosphorylation

- (photophosphorylation, is, light-driven ATP synthesis)
- (noncyclic photophosphorylation, produces, ATP)
- (noncyclic photophosphorylation, produces, NADPH)
- (noncyclic photophosphorylation, produces, oxygen)
- (cyclic photophosphorylation, produces, ATP)
- (cyclic photophosphorylation, does not produce, NADPH)
- (cyclic photophosphorylation, does not produce, oxygen)
- (cyclic electron flow, involves, PSI)
- (cyclic electron flow, helps balance, ATP/NADPH ratio)

### Calvin cycle and carbon fixation

- (Calvin cycle, is also called, Calvin-Benson cycle)
- (Calvin cycle, is also called, Calvin-Benson-Bassham cycle)
- (Calvin cycle, occurs in, chloroplast stroma)
- (Calvin cycle, uses, ATP)
- (Calvin cycle, uses, NADPH)
- (Calvin cycle, fixes, carbon dioxide)
- (Calvin cycle, produces, glyceraldehyde-3-phosphate)
- (glyceraldehyde-3-phosphate, is abbreviated as, G3P)
- (Calvin cycle, has phase, carbon fixation)
- (Calvin cycle, has phase, reduction)
- (Calvin cycle, has phase, regeneration of RuBP)

### Calvin cycle enzymes and intermediates

- (RuBisCO, catalyzes, carboxylation of RuBP)
- (RuBisCO, is full name, ribulose-1,5-bisphosphate carboxylase/oxygenase)
- (RuBP, is full name, ribulose-1,5-bisphosphate)
- (carbon dioxide, combines with, RuBP)
- (carboxylated RuBP intermediate, splits into, two 3-phosphoglycerate molecules)
- (3-phosphoglycerate, is abbreviated as, 3-PGA)
- (3-phosphoglycerate, is reduced to, glyceraldehyde-3-phosphate)
- (some G3P, exits cycle for, sugar synthesis)
- (most G3P, is used for, RuBP regeneration)
- (RuBP regeneration, requires, ATP)

### Stoichiometry and energetic cost

- (fixation of one CO2 in Calvin cycle, consumes, 3 ATP)
- (fixation of one CO2 in Calvin cycle, consumes, 2 NADPH)
- (production of one net G3P, requires fixation of, 3 CO2)
- (production of one net G3P, consumes, 9 ATP)
- (production of one net G3P, consumes, 6 NADPH)
- (production of one glucose equivalent, requires fixation of, 6 CO2)
- (production of one glucose equivalent, consumes, 18 ATP)
- (production of one glucose equivalent, consumes, 12 NADPH)

### Sugar and carbohydrate metabolism

- (G3P, can be converted into, glucose)
- (G3P, can be converted into, sucrose)
- (G3P, can be converted into, starch)
- (starch, serves as, storage carbohydrate in plants)
- (sucrose, serves as, transport sugar in many plants)
- (photosynthetic carbon products, support, respiration)
- (photosynthetic carbon products, support, growth)
- (photosynthetic carbon products, support, biosynthesis)
- (cellulose, is synthesized from, photosynthetically derived sugars)

### Limiting factors

- (photosynthesis rate, depends on, light intensity)
- (photosynthesis rate, depends on, carbon dioxide concentration)
- (photosynthesis rate, depends on, temperature)
- (photosynthesis rate, depends on, water availability)
- (photosynthesis rate, depends on, nutrient availability)
- (photosynthesis rate, depends on, chlorophyll content)
- (low light, can limit, photosynthesis)
- (low CO2, can limit, photosynthesis)
- (water stress, can reduce, photosynthesis)
- (extreme temperatures, can reduce, photosynthesis)
- (nitrogen deficiency, can reduce, photosynthesis)
- (magnesium deficiency, can reduce, chlorophyll synthesis)

### Light response and saturation

- (photosynthesis rate, generally increases with, light intensity at low light)
- (photosynthesis rate, reaches, light saturation point)
- (very high light, can cause, photoinhibition)
- (photosynthetic organisms, acclimate to, changing light conditions)
- (shade leaves, often have, lower light saturation point)
- (sun leaves, often have, higher photosynthetic capacity)

### Action spectrum and absorption spectrum

- (action spectrum of photosynthesis, describes, effectiveness of wavelengths)
- (absorption spectrum of pigments, describes, light absorption by wavelength)
- (red light, is effective for, photosynthesis)
- (blue light, is effective for, photosynthesis)
- (green light, is less efficiently used than, red or blue light)
- (Engelmann experiment, demonstrated, action spectrum of photosynthesis)

### Gas exchange and measurements

- (photosynthesis, consumes, carbon dioxide)
- (photosynthesis, releases, oxygen)
- (net photosynthesis, equals, gross photosynthesis minus respiration)
- (compensation point, is where, photosynthesis equals respiration)
- (gas exchange measurements, can estimate, photosynthetic rate)
- (chlorophyll fluorescence, can indicate, photosystem performance)
- (oxygen evolution, can indicate, photosynthetic activity)
- (carbon isotope discrimination, can provide information about, photosynthetic pathway)

### Photorespiration

- (RuBisCO, also catalyzes, oxygenation of RuBP)
- (oxygenation of RuBP, initiates, photorespiration)
- (photorespiration, consumes, oxygen)
- (photorespiration, releases, carbon dioxide)
- (photorespiration, consumes, energy)
- (photorespiration, generally reduces, photosynthetic efficiency)
- (photorespiration, is favored by, high temperature)
- (photorespiration, is favored by, low CO2/O2 ratio)
- (photorespiration, increases when, stomata close)
- (photorespiration pathway, involves, chloroplast)
- (photorespiration pathway, involves, peroxisome)
- (photorespiration pathway, involves, mitochondrion)

### C3 photosynthesis

- (C3 photosynthesis, is the most common, photosynthetic pathway)
- (C3 plants, fix CO2 initially into, 3-phosphoglycerate)
- (C3 plants, use, Calvin cycle directly in mesophyll cells)
- (C3 plants, include, wheat)
- (C3 plants, include, rice)
- (C3 plants, include, soybean)
- (C3 plants, are more prone to, photorespiration)

### C4 photosynthesis

- (C4 photosynthesis, is adaptation to, high light and high temperature)
- (C4 plants, initially fix CO2 into, four-carbon compounds)
- (C4 plants, use enzyme, PEP carboxylase for initial fixation)
- (PEP carboxylase, has high affinity for, bicarbonate)
- (PEP carboxylase, is not inhibited by, oxygen)
- (initial C4 acids, include, oxaloacetate)
- (initial C4 acids, include, malate)
- (initial C4 acids, include, aspartate)
- (C4 pathway, concentrates CO2 around, RuBisCO)
- (C4 pathway, reduces, photorespiration)
- (many C4 plants, exhibit, Kranz anatomy)
- (Kranz anatomy, separates, mesophyll and bundle sheath functions)
- (mesophyll cells in C4 plants, perform, initial CO2 fixation)
- (bundle sheath cells in C4 plants, perform, Calvin cycle)
- (C4 plants, include, maize)
- (C4 plants, include, sugarcane)
- (C4 plants, include, sorghum)

### CAM photosynthesis

- (CAM photosynthesis, is adaptation to, arid conditions)
- (CAM, stands for, crassulacean acid metabolism)
- (CAM plants, open stomata at, night)
- (CAM plants, close stomata during, day)
- (CAM plants, fix CO2 at night into, organic acids)
- (malic acid, accumulates in, vacuoles of CAM plants)
- (CAM plants, release CO2 internally during, day)
- (CAM pathway, improves, water-use efficiency)
- (CAM plants, include, cacti)
- (CAM plants, include, pineapple)
- (CAM plants, include, many succulents)

### Ecological significance

- (photosynthesis, drives, primary productivity)
- (photosynthesis, forms base of, many food webs)
- (photosynthesis, removes CO2 from, atmosphere)
- (photosynthesis, influences, global carbon cycle)
- (photosynthesis, influences, oxygen cycle)
- (terrestrial photosynthesis, occurs mainly in, forests and grasslands)
- (aquatic photosynthesis, occurs in, oceans)
- (aquatic photosynthesis, occurs in, lakes)
- (phytoplankton photosynthesis, contributes substantially to, global oxygen production)
- (photosynthesis, moderates, atmospheric CO2 levels)
- (photosynthesis, contributes to, biomass accumulation)

### Evolutionary significance

- (oxygenic photosynthesis, evolved in, cyanobacteria)
- (cyanobacteria, caused, Great Oxidation Event)
- (Great Oxidation Event, increased, atmospheric oxygen)
- (rise of atmospheric oxygen, enabled, aerobic metabolism)
- (rise of atmospheric oxygen, enabled, ozone layer formation)
- (chloroplasts, originated by, endosymbiosis)
- (chloroplasts, evolved from, cyanobacterial ancestor)
- (primary endosymbiosis, gave rise to, plastids)
- (secondary endosymbiosis, spread plastids among, diverse eukaryotes)

### Endosymbiosis and plastids

- (plastids, include, chloroplasts)
- (chloroplasts, contain, circular DNA)
- (chloroplasts, contain, bacterial-like ribosomes)
- (chloroplasts, divide by, binary fission-like process)
- (chloroplasts, support, endosymbiotic origin hypothesis)
- (glaucophytes, possess, primary plastids)
- (red algae, possess, primary plastids)
- (green algae, possess, primary plastids)
- (land plants, inherited plastids from, green algal lineage)

### Differences among photosynthetic bacteria

- (anoxygenic photosynthetic bacteria, use, one photosystem-like reaction center)
- (purple bacteria, perform photosynthesis in, intracytoplasmic membranes)
- (green sulfur bacteria, use, bacteriochlorophyll)
- (purple bacteria, use, bacteriochlorophyll)
- (b
