what is mechanism of photosynthesis

Q- What is mechanism of photosynthesis?

Answer:- the study of photosynthesis demonstrated the existence of two face:-

ü  Light Reaction

ü  Dark Reaction

The light reaction required sun light is called photochemical reaction. Whereas reaction which take place in absence of sunlight are called chemical reaction.

Ø  Light reaction:

Absorption of light energy by chlorophyll:- during the light reaction solar energy is trapped by chlorophyll and accessory pigments. Chlorophyll pigment absorbs light energy which can emit the electron and release of energy in the form of photon and quantum.

Note:- Photon and Quantam are pockets of energy which emit by light.

Ø  Conversion of light energy, chemical energy and splitting of water:- Formation of ATP ( Adinosine Triphosphate ) formation of ATP from ADP joining a phosphate group in the presence of sunlight is called photophosphorlation. These ATP can be used in the dark reaction.


Ø  Photolysis of water:- the decomposition of water into hydrogen and oxygen is called phohtolysis.


Water + Energy = Hydrogen + Oxygen


Ø  Synthesis of NADPH:- Nicotinamide Adenine Dinucleotide Phosphtae.


Dark Reaction:-

Ø  Reduction of CO2 to glucose:- CO2 is reduced to glucose by the Hydrogen in NADPH and utilized the chemical energy in form of ATP.

Ø  RUBP + CO2 + NADPH + ATP = RUBP + C6H12O6 + ADP + NADPH + PO4.

ATP and NADPH are called assimilatory power.

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