Photosynthesis pt 2 Flashcards
What are the chief components of the light reactions of photosynthesis?
Photosystems 1 & 2, the cytochrome b6/f complex, and the ATP synthase complex.
The interior space inside the sacs and tubes of the thylakoids is referred to as the ____
Lumen
What is the role of photosystem II in the light reactions of photosynthesis?
removes electrons from water, energizes them & passes them to the cytochrome b6/f complex, and releases the protons that result as H20 splits into the thylkakoid lumen
What is the role of photosystem I in the light reactions of photosynthesis?
receives electrons that have passed through the cytochrome b6/f complex, energizes then, & passes them to an electron transport system leading to NADPH (or sometimes back to the cyt. b6/f complex).
What is the role of the cytochrome b6/f complex in the light reactions of photosynthesis?
pumps protons into the thylakoid lumen as a result of electron flow.
How is ATP generated during the light reactions of photosynthesis?
electrical flow drives protons into the thylakoid lumen; these diffuse back to the chloroplast stroma through the ATP synthase complex, which rotates & phosphorylates ADP.
How do electrons flow during the non-cyclic variant of the light reactions of photosynthesis?
water→Photosystem II → cytochrome b6/f complex → photosystem I → NADPH.
What is the energy-product obtained during the light reactions of photosynthesis?
Both ATP & NADPH
How do chloroplasts obtain extra ATP to achieve an optimal ATP / NADPH ratio for the carbon fixation reactions?
all of the options except the ‘none’ option are true
During what stage of the light reactions is oxygen released?
the water splitting reaction in photosystem II
Where in the chloroplast do the light reactions occur?
on the Thylakoid membranes
What are granna?
Stacks of thylakoids
