Photosynthesis

Absorption of Light.

What is photosynthesis?

• Absorption of light in the mitochondria that produces glucose.

• Chloroplasts capture light energy in the thylakoids.

• The pigments are found in the thylakoids (why 4 pigments?).

• Majority of light is absorbed with chlorophyll A and B.

Phase I: Light Dependent RXNS

• 2 parts involved: photosystem I and II.

• Light energy is absorbed in photosystem II which excites electrons and splits water into Hydrogen and oxygen and releases electrons.

• Excited electrons move from photsystem II to photosystem I along a transport chain.

• Photo I prduces energy in the form of ATP.

Phase II: Calvin Cycle

• Also called the Dark reactions or light independent reactions.

• This is where the Carbon dioxide comes into play along with the ATP produced in the light reactions.

• It takes six cycles through Calvin cycle to produce the end product.

• Where else does the ATP come from in plants?

Calvin Cycle