Photosynthesis Flashcards
What does ATP provide in the reactions?
chemical energy
What does NADPH provide in the reactions?
reducing power
Parts of chloroplast important in photosynthesis
Stroma
Thylakoid membranes
What light wavelength used in photosystem 1?
700nm
What light wavelength used in photosystem 2?
680nm
Name the three main electron carriers in the light reaction:
Plastoquinone (Q)
Plastocyanin
Ferridoxin
When an electron transporter gains an electron, it has been ______.
Reduced
From where to where does plastoquinone transfer electrons?
Light reaction
From photosystem 2 to cytochrome bf complex
From where to where does plastocyanin transfer electrons?
Light reaction
From cytochrome bf complex to photosystem 2
Where does the light reaction occur?
From the stroma, across the thylakoid membrane into the lumen of the thylakoid
Where does the Calvin cycle (light-independent reaction) take place?
In the stroma of chloroplasts
What does the cytochrome bf complex do?
Pump H+ into lumen when receives electron
What can plastoquinone transfer at one time?
2e- and 2H+
What can plastocyanin transfer at one time?
1e-
Where is plastocyanin found?
The lumen
Where is plastoquinone found?
The stroma
Where is ferridoxin found?
The stroma
What does ferridoxin do?
Transfer electrons from photosystem 1 to covert NADP+ into NADPH
What does the light reaction provide for the dark reaction?
NADPH and ATP
What are the three parts of the dark reaction (in order)?
- Fixation
- Reduction of PGA to G3P
- Regeneration of RuBP from G3P
How is calvin cycle regulated?
Ferridoxin is regulated
RuBisCo is activated by CO2 (1) and Mg2+ (2)
- Mg2+ moves into stroma as H+ pumped into thylakoids in light reaction
What is photorespiration?
When RuBisCo attaches O2 (not CO2) to RuBP
Why is photorespiration bad?
It makes 2-phosphoglycerate instead of 3-phosphoglycerate and takes more reactions and ATP to convert 2-phosphoglycerate into 3-phosphogylcerate
