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ENERGY TRANSFORMATION

Light Reactions

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Photosynthesis
Light Reactions
The Calvin Cycle
Cellular Respiration
Glycolysis and Fermentation
Aerobic Respiration
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The light reactions, which take place in the thylakoid membrane, use energy from sunlight to produce ATP and NADPH, and oxygen.

Step 1: Light energy forces electrons to enter a higher energy level in the two chlorophyll a molecules of photosynthesis II.
 
Step 2: Because molecules have been lost the chlorophyll a molecules have undergone an oxidation reaction. Each oxidation reaction must be accompanied by a reduction reaction. So, a substance have to accept electrons that the chlorophyll a molecules have lost.
 
Step 3: The primary electron acceptor donates that electron to the first of the series of molecules located in the thylakoid membrane. Those moles are called an electron transport chain. 
 
Step 4: Light is absorbed by photosytem I, which happens at the same time that light is absorbed by Photosystem II.
 
Step 5: NADP+ is reduced to NADPH by a reaction called oxidation/reduction reactions.