photosynthesis...

[guitarian]

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how did RuBP and glucose were produced from PGAL in the light reaction...knowing that PGAL is from 2 PGA...

[jamesmusslewhite]

3-phosphoglyceraldehyde or PGAL is 3-carbon glyceraldehyde 3-phosphate. The PGA produced by this first step of the light independent reaction is converted to PGAL by using the energy in ATP and the reducing power of NADPH. This returns ADP, Pi, and NADP+ to the light reactions for their continued functioning.
PGAL can then be converted to glucose. RUBP is regenerated for the cycle to continue. 6 CO2 + 6 RUBP (+ energy from 12 ATP and 12 NADPH) ----- 12 PGAL (3-carbon)-----10 PGAL (+ energy from 6 ATP) ----- 6 RUBP (ie starting material regenerated)------2 PGAL-----glucose (6-carbon).


This process is strictly produced in nature, because photosynthesis has never be artificially produced in a lab. If it could be produced it could help feed the world's poor. It would be a cheap food source. A plant only needs rudimentary nutrients and water to be absorbed by the roots, transferred through the Zilum to cells in the leaf. Sunlight striking the leaf activates these cells, which produce chloroplast (sugars) which the plant moves through the floum back to the roots.