How are photosystems 1 and 2 linked to one another?
Each photosystem consists of two closely linked components: the first is the antenna complex formed by hundreds of pigment molecules that capture photons and transfer the harvested light energy to the second component named the reaction center, which possesses Chl a molecules in a matrix of protein.
How are the two photosystems connected?
In photosynthesis, two energy converting photosystems are connected, electrochemically, in series. The connecting electron carriers are oxidized by photosystem I (PS I) and reduced by photosystem II (PS II).
What are photosystems I and II and how are they related quizlet?
Photosystem I produces NADPH, which is similar in function to the NADH and FADH2 produced by the citric acid cycle. NADPH is an electron carrier that can donate electrons to other compounds and thus reduce them. Photosystem II produces a proton gradient that drives the synthesis of ATP.
What is the function of the photosystems II and I?
During this process, the water-splitting and oxygen-evolving reaction is catalyzed by photosystem II (PSII), while photosystem I (PSI) generates the reducing power for the reduction of NADP+ to NADPH.
How does photosynthesis I and II happen?
The movement of electrons in Photosystems I and II and the action of an enzyme split the water into oxygen, hydrogen ions, and electrons. These reactions occur in the stroma, the fluid in the chloroplast surrounding the thylakoids, and each step is controlled by a different enzyme.
What are the two types of photosystems?
There are two types of photosystems in cyanobacteria, algae and higher plants, called photosystem I (PSI, plastocyanin-ferredoxin oxidoreductase) and photosystem II (PSII, water-plastoquinone oxidoreductase), both of which are multisubunit membrane complexes.
Is glucose used in photosystem 2?
Photosystem II is the first link in the chain of photosynthesis. It captures photons and uses the energy to extract electrons from water molecules. Finally, the electrons are placed on a carrier molecule, NADPH, which delivers them to enzymes that build sugar from water and carbon dioxide.
What are the 2 photosystems necessary?
Both photosystems I and II are required for oxygenic photosynthesis. Oxygenic photosynthesis can be performed by plants and cyanobacteria; cyanobacteria are believed to be the progenitors of the photosystem-containing chloroplasts of eukaryotes.
What are the products of photosystem I and II?
Cards
| Term Energy | Definition The ability to do work |
|---|---|
| Term Photophosphorylation | Definition adding a phosphate to ADP to form ATP using light |
| Term What are the product(s) of photosystem II? | Definition oxygen ATP |
| Term What are the product(s) of photosystem I? | Definition NADPH |
What is the purpose of photosystem I?
Photosystem I is an integral membrane protein complex that uses light energy to catalyze the transfer of electrons across the thylakoid membrane from plastocyanin to ferredoxin. Ultimately, the electrons that are transferred by Photosystem I are used to produce the high energy carrier NADPH.
What’s the difference between photosystem I and II?
It involves the P700, chlorophyll and other pigments, while PS II is the complex that absorbs light energy, involving P680, chlorophyll and accessory pigments and transfer electrons from water to plastoquinone and thus work in dissociation of water molecules and produces protons (H+) and O2.
How are electrons transferred to photosystems I and II?
The light reactions of photosystems I and II (PSI and PSII) result in the formation of an electrochemical transmembrane proton gradient that is used for the production of ATP. Electrons that are subsequently transferred from PSI via the soluble protein ferredoxin to ferredoxin-NADP+…
How many photons are absorbed by photosystem II?
It requires a lot of energy to break the bonds in a water molecule—much more energy than a single photon of light contains. A manganese-containing complex in photosystem II absorbs four photons, one at a time, and passes four electrons, one at a time, back to the reaction center, P680.
What happens in the light reaction of photosystem II?
The light reactions of photosystems I and II (PSI and PSII) result in the formation of an electrochemical transmembrane proton gradient that is used for the production of ATP. Electrons that are subsequently transferred from PSI via the soluble protein ferredoxin to ferredoxin-NADP+ reductase that reduces NADP + to NADPH.