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Photosynthesis (光合成)

Mount Usu / Sarobetsu post-mined peatland
From left: Crater basin in 1986 and 2006. Cottongrass / Daylily

Life is woven from the air by light

That is the conversion from light energy to chemical energy (stocked into carbohydrates, represented by glucose, sucrose and starch) by green plants.
6CO2 + 12H2O + [solar energy] → C6H12O6 + 6O2 + 6H2O
carbon dioxide + water + [solar energy] → glucose + oxygen + water
Do not understand by the simplified equation. You can not understand why water is important, although you might learn this equation when you were in high school.

6CO2 + 6H2O + [solar energy] → C6H12O6 + 6O2

Characteristics of photosynthesis on terrestrial vascular plants

CO2, 6 moles = 134.4 liters at standard temperature and pressure
Fig. Photosynthesis for making budget
Visible light (solar radiation) → absorbed by leaves
Water → absorbed from soil (土壌) (or water) by roots ()

[ metabolism ]


Metabolism patterns on photosynthesis (光合成における代謝様式)

Carvin-Benson cycle (カルビン=ベンソン回路)


Ecophysiology of photosynthesis (光合成の生理生態)

Photosynthetic nitrogen-use efficiency (PNUE)
the ratio of CO2 assimilation rate to leaf organic nitrogen content

Carbohydrate and metabolism (炭酸同化と代謝)

C3 plant (C3植物)
photorespiration present
spinach, peanuts, cotton, wheat, rice, barley and most trees and grasses
C4 plant (C4植物)
= Hatch-Slack pathway (Hatch & Slack 1966)
photorespiration absent

C4 plants            Sjoa  Sunflower  Sugar  Tobacco  Corn
                     bean             beat

Optimal               26      25       25       25      35
temperature (°C)
O2 fixation           35      28      25        11      55
(CO2 mg/dm2/h)
Photorespiration      46      27       47       55       0
(lost O2 %)

+ sugar cane, millet, sorghum, pineapple, daisies, cabbage, etc.

CAM plant (CAM植物)
= crassulacean acid metabolism
cacti, sedum, jade, orchids and agave

Photoinhibition (光阻害)

Light-induced reduction in the photosynthetic capacity of a plant, alga, and cyanobacterium
≈ light-induced damage to PSII ∵ photosystem II (PSII) is most sensitive
Pulse amplitude modulation, PAM(パルス変調蛍光測定)