Light dependent reaction

the energy is used for two purposes

• make ATP

• split water into OH- and H+ ions via photolysis (using light)

what happens to electrons when chlorophyll absorbs light energy

they become excited, and leave chlorophyll molecule.

what happens when electrons leave chlorophyll molecule

it becomes ionised via photoionisation, the electrons that leave the chlorophyll are taken up by an electron carrier

what has been oxidised and reduced

chlorophyll is oxidised

electron carrier is reduced

where do electron carriers form a transfer chain

in the thykaloids

summarise the chemiosmatic theory

• each thylakoids is an enclosed chamber into which protons are pumped into stroma using protein carriers in the thylakoid membrane

• the energy is from the electrons released during photolysis

• photolysis also produces protons which further increase the concentration in the thylakoid space

• This creates a concentration gradient, the protons can only cross through ATP synthase channel proteins

• as protons pass through, they cause changes in the structure of the enzyme and catalyse ADP + Pi → ATP

show photolysis of water equation

2H2O +> 4e- + 4H+ + O2

what are the electron carriers called

NADP

what happens to NADP when it gains these protons

it becomes reduced

how are chloroplasts adapted to their function

• thylakoid membranes provide a large surface area for attachment of chlorophyll, electron carriers and enzymes

• the granal membranes have ATP synthase channels within them, which produce ATP

• chloroplasts contain dna and ribosomes that can produce proteins needed for LDR