Biochemistry - Photosynthesis Flashcards
What type of reaction is photosynthesis?
Endergonic, using photon light energy
What are the two seperate reactions of photosynthesis?
Dark and Light reactions
Dark reactions
Utilise NADPH and ATP generated by light-dependent electron transport
Where does Dark reaction occur?
Chloroplast storma
Where is CO2 uptake mediated?
Stomata in the lower epidermis
What is stomata size regulated by?
Guard cells
What is the structure of chloroplasts?
Two membranes enclosing thestroma, containing thylakoid where PS takes place
Overview of the light reactions
Transfer of electrons from water to NADP forming NADPH, coupled with proton transfer and subsequent ADP phosphorylation
Overview of the Calvin Cycle
ATP and NADHP convert CO2 into carbohydrates, regenrating NADH and ADP
Photosystem II
A membrane supercomplex, capturing sunlight catalysing water oxidation
First step in light reactions?
Photosystem II splitting water
What does PSII reduce?
Plastoquinone to Plastoquinol
Plastoquinol
The primary electron carrier in plants.
What does plastoquinol do after reduction?
Carrier electrons to cytochrome b6f
Cytochrome b6f
Oxidises plastoquinol to plastoquinone, whilst reducing plastocyanin
Plastocyanin
A redox protein in photosyntehsis carrying electrons from cytochrome b6f to photosystem i