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* Light is absorbed by the antenna pigments of photosystems II and I. * The absorbed energy is transferred to the reaction center chlorophylls, P680 in photosystem II, P700 in photosystem I. * Absorption of 1 photon of light by Photosystem II removes 1 electron from P680. * With its resulting positive charge, P680 is sufficiently electronegative that it can remove 1 electron from a molecule of water. * When these steps have occurred 4 times, requiring 2 molecules of water, 1 molecule of oxygen and 4 protons (H+) are released * The electrons are transferred (by way of plastoquinone - PQ in the figure) to the cytochrome b6/f complex where they provide the energy for chemiosmosis. * Activation of P700 in photosystem I enables it to pick up electrons from the cytochrome b6/f complex (by way of plastocyanin - PC in the figure) and raise them to a sufficiently high redox potential that, after passing through ferredoxin(Fd in the figure), * they can reduce NADP+ to NADPH. The sawtooth shifts in redox potential as electrons pass from P680 to NADP+ have caused this system to be called the Z-Scheme(although as I have drawn the diagram, it looks more like an "N"). It is also called noncyclic photophosphorylation because it produces ATP in a one-way process
What else can I help you with?
What sequence accurately reflects the flow of electrons in photosynthesis?
In photosynthesis, electrons flow from water molecules to photosystem II, then to photosystem I, and finally to NADP+ ultimately producing NADPH. Along the way, the electrons generate a proton gradient that drives ATP production.
Where does photosystem 2 and photosystem 1 occur?
Photosystem 2 is located in the thylakoid membrane of the chloroplasts, while Photosystem 1 is located downstream from Photosystem 2 in the thylakoid membrane. Both photosystems are important for light-dependent reactions during photosynthesis.
How do photosystem 1 and 2 allow the calvin cycle to work?
No. Photosystems I and II are where light-dependent reactions occur, while the Calvin Cycle is where light-independent reactions occur. Photosynthesis begins with Photosystem II, then Photosystem I, then the products from there go to the Calvin Cycle. (yes photosystem II comes before photosystem I)
What protein complex absorbs in energy that used to produce NADPH?
Photosystem 1
How are photosynthesis 1 and photosynthesis 2 similar?
Did you mean Photysystem I and Photosystem II. They both are overall identical except that Photosystem I is actually a later part of the process of Photosynthesis than Photosystem II, its only called Photosystem I because it was discovered first. Photosynthesis starts when light excites Photosystem II causing it to break up H20 that comes from the roots into H2 and 02. (If you are wondering why oxygen becomes two molecules when in H20 there is only one molecule of it, that is because it cannot exist as one molecule stably therefore it bonds with another oxygen from another break down almost instantly.) Then Photosystem II sends electrons across the electron transport pathway (along the membrane of the Thylakoid in between the two photosystems) to Photosystem I which then uses them to convert NaDP+ into NaDPH by adding a phosphate group from outside the Thylakoid. Thats pretty much what each Photosystem does and both are located inside the Thylakoid membrane.
Which photosystem is used first in photosynthesis?
Photosystem 2 happens in photosynthesis before photosystem 1. However they are numbered in order of how they were discovered. Photosystem 1 was discovered before photosystem 2. In photosynthesis the order of them is 2 then 1. meaning that photosystem 1 was discovered 1st but photosystem 2 happens 1st in photosynthesis
What groups of molecule are involved in photosynthesis?
Photosystem
What molecule absorbs sunlight in photosynthesis?
Photosystem II
What sequence accurately reflects the flow of electrons in photosynthesis?
In photosynthesis, electrons flow from water molecules to photosystem II, then to photosystem I, and finally to NADP+ ultimately producing NADPH. Along the way, the electrons generate a proton gradient that drives ATP production.
What is the start of photosynthesis?
pigments in photosystem II absorb light
Is photosynthesis a system?
Photosynthesis is not a system. It is a process in plants. It is very important process.Photosynthesis is a process of making sugars from CO2 and water by using light energy. Photosystem I and photosystem II are involved in this process to transfer electrons across the membrane. Photosynthesis occurs in plants algae and certain bacteria.
Is photosystem 2 light dependent?
Yes, photosystem 2 is a light-dependent process in photosynthesis. It absorbs photons to initiate the light-dependent reactions of photosynthesis, where it helps generate oxygen and produce ATP and NADPH.
How does water participate in the light reactions of photosynthesis?
Donating electrons to photosystem 2
What is true about the light reaction?
photosynthesis begins when pigments in photosystem i absorb light.
What is the difference between photosystem one and two?
Photosystem I absorbs light best at a wavelength of 700 nm, while Photosystem II absorbs light best at a wavelength of 680 nm. Photosystem I transfers electrons to reduce NADP+ to NADPH, while Photosystem II replenishes electrons lost in the process of photosynthesis. Both photosystems work together in the light-dependent reactions of photosynthesis to ultimately produce ATP and NADPH.
What is a photosystem made up of and where is it located?
A photosystem is a complex of proteins and pigments, primarily chlorophyll, that facilitates the capture of light energy during photosynthesis. There are two types of photosystems: Photosystem I (PSI) and Photosystem II (PSII), both of which are located in the thylakoid membranes of chloroplasts in plant cells. These structures play a crucial role in converting light energy into chemical energy, driving the process of photosynthesis.
Water participates directly in the light reactions of photosynthesis by?
Water participates directly in the light reactions of photosynthesis by donating electrons to photosystem II during the process of photolysis. These electrons are used to replace the ones lost by chlorophyll when it absorbs light energy, allowing the photosystem to continue absorbing light and generating ATP and NADPH for the Calvin cycle.
