-light independent

-produces the sugar PGAL 

-CO2 enteres Calvin Cycle and attaches to Ribulose Biphosphate (5 carbon sugar)

-RuBP + CO2 forms a 6 carbon molecule

 -6 carbon molecule breaks down to 2 3-phosphoglycerate

produce compound 3-PGA, rather than PGAL

- 

Dry environment plants

1. C02 combines with 3 carbon molecule PEP (phosphoenolpyruvate)

2. 4 carbon molecule Oxaloacetate is formed

-Bundle-sheath cells lie under mesophyll cells  

crassulacean acid metabolism

 dry conditions

-keep somatas closed during day and open at night(reverse of normal plants) 

electrons enter 2 electron transport chains

ATP and NADPH are formed  

P-680

energy is absorbed be P680.

electrons from the double bonds in the head of chlorophyll a become energized and move to a higher energy level 

captured by primary electron acceptor 

water is split apart, replacing electrons lost from chlorophyll a in P680

2 oxygen molecules join together to be a by product

electrons from P680 pass along a chain consisting of  plastoquione (PQ) (2 cytochromes and several other proteins)

end up in P700

provides energy to produce ATP by chemiosmosis 

photosystem I

P700

electrons that excape are replaced from P680

this ETC contains ferrodoxin and ends with production of NADPH