Question

How many photons does it take to fully reduce one molecule of nadp+ to nadph?

Answer 1

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It is known that 8 photons of light are used to produce 3ATP and 2NADPH molecules which is equivalent to 6 ATP molecules in total.

Answer 2

To produce the 3ATP and 2NADPH molecules, 8 photons of light are used

Explanation:  

• NAD + and NADP + are hydrogen-transferring cofactors that always work in conjunction with an enzyme.
• They are therefore also called coenzymes.
• The redox couple NADP + / NADPH + H + occurs in the chloroplasts;
• NADP + is the final acceptor of electrons and a proton in the course of photosynthetic electron transport (NAD + / NADH + H + is involved in the respiratory chain in the mitochondria; NADH + H + is the electron and proton donor of the electron transport chain in cell respiration.)
• The redox reaction:  NADP + + 2e - + 2H + <---> NADPH + H +
• One of the protons is bound directly to the nicotinamide ring by the NADP + , the other remains in the solution.